content/browser/snapshot_browsertest.cc - chromium/src - Git at Google

 // Copyright 2017 The Chromium Authors
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include <stddef.h>

 #include <algorithm>
 #include <map>
 #include <vector>

 #include "base/command_line.h"
 #include "base/containers/contains.h"
 #include "base/functional/bind.h"
 #include "base/memory/raw_ptr.h"
 #include "base/rand_util.h"
 #include "base/run_loop.h"
 #include "base/strings/stringprintf.h"
 #include "build/build_config.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/public/test/browser_test.h"
 #include "content/public/test/browser_test_utils.h"
 #include "content/public/test/content_browser_test.h"
 #include "content/public/test/content_browser_test_utils.h"
 #include "content/shell/browser/shell.h"
 #include "content/shell/common/shell_switches.h"
 #include "gpu/command_buffer/service/gpu_switches.h"
 #include "net/test/embedded_test_server/http_request.h"
 #include "net/test/embedded_test_server/http_response.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/gfx/image/image.h"

 namespace content {

 namespace {

 static const char kCanvasPageString[] =
     "<body>"
     "  <canvas id=\"canvas\" width=\"64\" height=\"64\""
     "    style=\"position:absolute;top:0px;left:0px;width:100%;"
     "    height=100%;margin:0;padding:0;\">"
     "  </canvas>"
     "  <script>"
     "    window.ctx = document.getElementById(\"canvas\").getContext(\"2d\");"
     "    function fillWithColor(color) {"
     "      ctx.fillStyle = color;"
     "      ctx.fillRect(0, 0, 64, 64);"
     "      return color;"
     "    }"
     "    var offset = 150;"
     "    function openNewWindow() {"
     "      window.open(\"/test\", \"\", "
     "          \"top=\"+offset+\",left=\"+offset+\",width=200,height=200\");"
     "      offset += 50;"
     "      return true;"
     "    }"
     "    window.document.title = \"Ready\";"
     "  </script>"
     "</body>";
 }

 class SnapshotBrowserTest : public ContentBrowserTest {
  public:
   SnapshotBrowserTest() {}

   void SetUpCommandLine(base::CommandLine* command_line) override {
     // Use a smaller browser window to speed up the snapshots.
     command_line->AppendSwitchASCII(::switches::kContentShellHostWindowSize,
                                     "200x200");
   }

   void SetUp() override {
     // These tests rely on the harness producing pixel output.
     EnablePixelOutput();
     ContentBrowserTest::SetUp();
   }

   content::WebContentsImpl* GetWebContents(Shell* browser) {
     return static_cast<content::WebContentsImpl*>(browser->web_contents());
   }

   content::RenderWidgetHostImpl* GetRenderWidgetHostImpl(Shell* browser) {
     return GetWebContents(browser)->GetRenderViewHost()->GetWidget();
   }

   void SetupTestServer() {
     // Use an embedded test server so we can open multiple windows in
     // the same renderer process, all referring to the same origin.
     embedded_test_server()->RegisterRequestHandler(base::BindRepeating(
         &SnapshotBrowserTest::HandleRequest, base::Unretained(this)));
     ASSERT_TRUE(embedded_test_server()->Start());

     ASSERT_TRUE(
         NavigateToURL(shell(), embedded_test_server()->GetURL("/test")));
   }

   std::unique_ptr<net::test_server::HttpResponse> HandleRequest(
       const net::test_server::HttpRequest& request) {
     GURL absolute_url = embedded_test_server()->GetURL(request.relative_url);
     if (absolute_url.path() != "/test")
       return nullptr;

     std::unique_ptr<net::test_server::BasicHttpResponse> http_response(
         new net::test_server::BasicHttpResponse());
     http_response->set_code(net::HTTP_OK);
     http_response->set_content(kCanvasPageString);
     http_response->set_content_type("text/html");
     return http_response;
   }

   void WaitForAllWindowsToBeReady() {
     const std::u16string expected_title = u"Ready";
     // The subordinate windows may load asynchronously. Wait for all of
     // them to execute their script before proceeding.
     auto browser_list = Shell::windows();
     for (Shell* browser : browser_list) {
       TitleWatcher watcher(GetWebContents(browser), expected_title);
       const std::u16string& actual_title = watcher.WaitAndGetTitle();
       EXPECT_EQ(expected_title, actual_title);
     }
   }

   struct ExpectedColor {
     ExpectedColor() : r(0), g(0), b(0) {}
     bool operator==(const ExpectedColor& other) const {
       return (r == other.r && g == other.g && b == other.b);
     }
     uint8_t r;
     uint8_t g;
     uint8_t b;
   };

   void PickRandomColor(ExpectedColor* expected) {
     expected->r = static_cast<uint8_t>(base::RandInt(0, 256));
     expected->g = static_cast<uint8_t>(base::RandInt(0, 256));
     expected->b = static_cast<uint8_t>(base::RandInt(0, 256));
   }

   struct SerialSnapshot {
     SerialSnapshot() : host(nullptr) {}

     raw_ptr<content::RenderWidgetHost> host;
     ExpectedColor color;
   };
   std::vector<SerialSnapshot> expected_snapshots_;

   void SyncSnapshotCallback(content::RenderWidgetHostImpl* rwhi,
                             const gfx::Image& image) {
     for (auto iter = expected_snapshots_.begin();
          iter != expected_snapshots_.end(); ++iter) {
       const SerialSnapshot& expected = *iter;
       if (expected.host == rwhi) {
         const SkBitmap* bitmap = image.ToSkBitmap();
         SkColor color = bitmap->getColor(1, 1);

         EXPECT_EQ(static_cast<int>(SkColorGetR(color)),
                   static_cast<int>(expected.color.r))
             << "Red channels differed";
         EXPECT_EQ(static_cast<int>(SkColorGetG(color)),
                   static_cast<int>(expected.color.g))
             << "Green channels differed";
         EXPECT_EQ(static_cast<int>(SkColorGetB(color)),
                   static_cast<int>(expected.color.b))
             << "Blue channels differed";

         expected_snapshots_.erase(iter);
         break;
       }
     }
   }

   std::map<content::RenderWidgetHost*, std::vector<ExpectedColor>>
       expected_async_snapshots_map_;
   int num_remaining_async_snapshots_ = 0;

   void AsyncSnapshotCallback(content::RenderWidgetHostImpl* rwhi,
                              const gfx::Image& image) {
     --num_remaining_async_snapshots_;
     auto iterator = expected_async_snapshots_map_.find(rwhi);
     ASSERT_NE(iterator, expected_async_snapshots_map_.end());
     std::vector<ExpectedColor>& expected_snapshots = iterator->second;
     const SkBitmap* bitmap = image.ToSkBitmap();
     SkColor color = bitmap->getColor(1, 1);
     bool found = false;
     // Find first instance of this color in the list and clear out all
     // of the entries before that point. If it's not found, report
     // failure.
     for (auto iter = expected_snapshots.begin();
          iter != expected_snapshots.end(); ++iter) {
       const ExpectedColor& expected = *iter;
       if (SkColorGetR(color) == expected.r &&
           SkColorGetG(color) == expected.g &&
           SkColorGetB(color) == expected.b) {
         // Erase everything up to this color, but not this color
         // itself, since it might be returned again later on
         // subsequent snapshot requests.
         expected_snapshots.erase(expected_snapshots.begin(), iter);
         found = true;
         break;
       }
     }

     EXPECT_TRUE(found) << "Did not find color ("
                        << static_cast<int>(SkColorGetR(color)) << ", "
                        << static_cast<int>(SkColorGetG(color)) << ", "
                        << static_cast<int>(SkColorGetB(color))
                        << ") in expected snapshots for RWH 0x" << rwhi;
   }
 };

 // Even the single-window test doesn't work on Android yet. It's expected
 // that the multi-window tests would never work on that platform.
 #if !BUILDFLAG(IS_ANDROID)

 #if BUILDFLAG(IS_MAC)
 // TODO(crbug.com/40854618): This test is flakey on macOS.
 #define MAYBE_SingleWindowTest DISABLED_SingleWindowTest
 #else
 #define MAYBE_SingleWindowTest SingleWindowTest
 #endif
 IN_PROC_BROWSER_TEST_F(SnapshotBrowserTest, MAYBE_SingleWindowTest) {
   SetupTestServer();

   content::RenderWidgetHostImpl* rwhi = GetRenderWidgetHostImpl(shell());

   for (int i = 0; i < 40; ++i) {
     SerialSnapshot expected;
     expected.host = rwhi;
     PickRandomColor(&expected.color);

     std::string colorString = base::StringPrintf(
         "#%02x%02x%02x", expected.color.r, expected.color.g, expected.color.b);
     std::string script = std::string("fillWithColor(\"") + colorString + "\");";
     EXPECT_EQ(colorString, EvalJs(GetWebContents(shell()), script));

     expected_snapshots_.push_back(expected);

     // Get the snapshot from the surface rather than the window. The
     // on-screen display path is verified by the GPU tests, and it
     // seems difficult to figure out the colorspace transformation
     // required to make these color comparisons.
     rwhi->GetSnapshotFromBrowser(
         base::BindOnce(&SnapshotBrowserTest::SyncSnapshotCallback,
                        base::Unretained(this), base::Unretained(rwhi)),
         true);
     while (expected_snapshots_.size() > 0) {
       base::RunLoop().RunUntilIdle();
     }
   }
 }

 // Timing out either all the time, or infrequently, apparently because
 // they're too slow, on the following configurations:
 //   Windows Debug
 //   Windows Release (https://crbug.com/1376441)
 //   Linux Chromium OS ASAN LSAN Tests (1)
 //   Linux TSAN Tests
 // See crbug.com/771119
 // TODO(crbug.com/40834774): Fix and enable on Fuchsia.
 #if BUILDFLAG(IS_WIN) || BUILDFLAG(IS_CHROMEOS) || BUILDFLAG(IS_FUCHSIA) || \
     (BUILDFLAG(IS_LINUX) && defined(THREAD_SANITIZER))
 #define MAYBE_SyncMultiWindowTest DISABLED_SyncMultiWindowTest
 #else
 #define MAYBE_SyncMultiWindowTest SyncMultiWindowTest
 #endif
 IN_PROC_BROWSER_TEST_F(SnapshotBrowserTest, MAYBE_SyncMultiWindowTest) {
   SetupTestServer();

   for (int i = 0; i < 3; ++i) {
     EXPECT_EQ(true, EvalJs(GetWebContents(shell()), "openNewWindow()"));
   }

   base::RunLoop().RunUntilIdle();

   WaitForAllWindowsToBeReady();

   auto browser_list = Shell::windows();
   EXPECT_EQ(4u, browser_list.size());

   for (int i = 0; i < 20; ++i) {
     for (int j = 0; j < 4; j++) {
       // Start each iteration by taking a snapshot with a different
       // browser instance.
       int browser_index = (i + j) % 4;
       Shell* browser = browser_list[browser_index];
       content::RenderWidgetHostImpl* rwhi = GetRenderWidgetHostImpl(browser);

       SerialSnapshot expected;
       expected.host = rwhi;
       PickRandomColor(&expected.color);

       std::string colorString =
           base::StringPrintf("#%02x%02x%02x", expected.color.r,
                              expected.color.g, expected.color.b);
       std::string script =
           std::string("fillWithColor(\"") + colorString + "\");";
       EXPECT_EQ(colorString, EvalJs(GetWebContents(browser), script));
       expected_snapshots_.push_back(expected);
       // Get the snapshot from the surface rather than the window. The
       // on-screen display path is verified by the GPU tests, and it
       // seems difficult to figure out the colorspace transformation
       // required to make these color comparisons.
       rwhi->GetSnapshotFromBrowser(
           base::BindOnce(&SnapshotBrowserTest::SyncSnapshotCallback,
                          base::Unretained(this), base::Unretained(rwhi)),
           true);
     }

     while (expected_snapshots_.size() > 0) {
       base::RunLoop().RunUntilIdle();
     }
   }
 }

 // Timing out either all the time, or infrequently, apparently because
 // they're too slow, on the following configurations:
 //   Windows Debug
 //   Linux Chromium OS ASAN LSAN Tests (1)
 //   Linux TSAN Tests
 // See crbug.com/771119
 // TODO(crbug.com/40740836): recently crashes flakily on
 // linux_chromium_asan_rel_ng and linux-rel.
 // TODO(crbug.com/40834774): Fix and enable on Fuchsia.
 #if (BUILDFLAG(IS_WIN) && !defined(NDEBUG)) || BUILDFLAG(IS_CHROMEOS) || \
     BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_FUCHSIA)
 #define MAYBE_AsyncMultiWindowTest DISABLED_AsyncMultiWindowTest
 #else
 #define MAYBE_AsyncMultiWindowTest AsyncMultiWindowTest
 #endif
 IN_PROC_BROWSER_TEST_F(SnapshotBrowserTest, MAYBE_AsyncMultiWindowTest) {
   SetupTestServer();

   for (int i = 0; i < 3; ++i) {
     EXPECT_EQ(true, EvalJs(GetWebContents(shell()), "openNewWindow()"));
   }

   base::RunLoop().RunUntilIdle();

   WaitForAllWindowsToBeReady();

   auto browser_list = Shell::windows();
   EXPECT_EQ(4u, browser_list.size());

   // This many pending snapshots per window will be put on the queue
   // before draining the requests. Anything more than 1 seems to catch
   // bugs which might otherwise be introduced in LatencyInfo's
   // propagation of the BROWSER_SNAPSHOT_FRAME_NUMBER_COMPONENT
   // component type.
   int divisor = 3;

   for (int i = 0; i < 10 * divisor; ++i) {
     for (int j = 0; j < 4; j++) {
       // Start each iteration by taking a snapshot with a different
       // browser instance.
       int browser_index = (i + j) % 4;
       Shell* browser = browser_list[browser_index];
       content::RenderWidgetHostImpl* rwhi = GetRenderWidgetHostImpl(browser);

       std::vector<ExpectedColor>& expected_snapshots =
           expected_async_snapshots_map_[rwhi];

       // Pick a unique random color.
       ExpectedColor expected;
       do {
         PickRandomColor(&expected);
       } while (base::Contains(expected_snapshots, expected));
       expected_snapshots.push_back(expected);

       std::string colorString = base::StringPrintf("#%02x%02x%02x", expected.r,
                                                    expected.g, expected.b);
       std::string script =
           std::string("fillWithColor(\"") + colorString + "\");";
       EXPECT_EQ(colorString, EvalJs(GetWebContents(browser), script));
       // Get the snapshot from the surface rather than the window. The
       // on-screen display path is verified by the GPU tests, and it
       // seems difficult to figure out the colorspace transformation
       // required to make these color comparisons.
       rwhi->GetSnapshotFromBrowser(
           base::BindOnce(&SnapshotBrowserTest::AsyncSnapshotCallback,
                          base::Unretained(this), base::Unretained(rwhi)),
           true);
       ++num_remaining_async_snapshots_;
     }

     // Periodically yield and drain the async snapshot requests.
     if ((i % divisor) == 0) {
       bool drained;
       do {
         drained = true;
         for (auto iter = expected_async_snapshots_map_.begin();
              iter != expected_async_snapshots_map_.end(); ++iter) {
           if (iter->second.size() > 1) {
             drained = false;
             break;
           }
         }
         if (!drained) {
           base::RunLoop().RunUntilIdle();
         }
       } while (!drained);
     }
   }

   // At the end of the test, cooperatively wait for all of the snapshot
   // requests to be drained before exiting. This works around crashes
   // seen when tearing down the compositor while these requests are in
   // flight. Likely, user-visible APIs that use this facility are safe
   // in this regard.
   while (num_remaining_async_snapshots_ > 0) {
     base::RunLoop().RunUntilIdle();
   }
 }

 #endif  // !BUILDFLAG(IS_ANDROID)

 }  // namespace content
	// Copyright 2017 The Chromium Authors
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include <stddef.h>

	#include <algorithm>
	#include <map>
	#include <vector>

	#include "base/command_line.h"
	#include "base/containers/contains.h"
	#include "base/functional/bind.h"
	#include "base/memory/raw_ptr.h"
	#include "base/rand_util.h"
	#include "base/run_loop.h"
	#include "base/strings/stringprintf.h"
	#include "build/build_config.h"
	#include "content/browser/renderer_host/render_view_host_impl.h"
	#include "content/browser/renderer_host/render_widget_host_impl.h"
	#include "content/browser/web_contents/web_contents_impl.h"
	#include "content/public/test/browser_test.h"
	#include "content/public/test/browser_test_utils.h"
	#include "content/public/test/content_browser_test.h"
	#include "content/public/test/content_browser_test_utils.h"
	#include "content/shell/browser/shell.h"
	#include "content/shell/common/shell_switches.h"
	#include "gpu/command_buffer/service/gpu_switches.h"
	#include "net/test/embedded_test_server/http_request.h"
	#include "net/test/embedded_test_server/http_response.h"
	#include "third_party/skia/include/core/SkBitmap.h"
	#include "ui/gfx/image/image.h"

	namespace content {

	namespace {

	static const char kCanvasPageString[] =
	"<body>"
	" <canvas id=\"canvas\" width=\"64\" height=\"64\""
	" style=\"position:absolute;top:0px;left:0px;width:100%;"
	" height=100%;margin:0;padding:0;\">"
	" </canvas>"
	" <script>"
	" window.ctx = document.getElementById(\"canvas\").getContext(\"2d\");"
	" function fillWithColor(color) {"
	" ctx.fillStyle = color;"
	" ctx.fillRect(0, 0, 64, 64);"
	" return color;"
	" }"
	" var offset = 150;"
	" function openNewWindow() {"
	" window.open(\"/test\", \"\", "
	" \"top=\"+offset+\",left=\"+offset+\",width=200,height=200\");"
	" offset += 50;"
	" return true;"
	" }"
	" window.document.title = \"Ready\";"
	" </script>"
	"</body>";
	}

	class SnapshotBrowserTest : public ContentBrowserTest {
	public:
	SnapshotBrowserTest() {}

	void SetUpCommandLine(base::CommandLine* command_line) override {
	// Use a smaller browser window to speed up the snapshots.
	command_line->AppendSwitchASCII(::switches::kContentShellHostWindowSize,
	"200x200");
	}

	void SetUp() override {
	// These tests rely on the harness producing pixel output.
	EnablePixelOutput();
	ContentBrowserTest::SetUp();
	}

	content::WebContentsImpl* GetWebContents(Shell* browser) {
	return static_cast<content::WebContentsImpl*>(browser->web_contents());
	}

	content::RenderWidgetHostImpl* GetRenderWidgetHostImpl(Shell* browser) {
	return GetWebContents(browser)->GetRenderViewHost()->GetWidget();
	}

	void SetupTestServer() {
	// Use an embedded test server so we can open multiple windows in
	// the same renderer process, all referring to the same origin.
	embedded_test_server()->RegisterRequestHandler(base::BindRepeating(
	&SnapshotBrowserTest::HandleRequest, base::Unretained(this)));
	ASSERT_TRUE(embedded_test_server()->Start());

	ASSERT_TRUE(
	NavigateToURL(shell(), embedded_test_server()->GetURL("/test")));
	}

	std::unique_ptr<net::test_server::HttpResponse> HandleRequest(
	const net::test_server::HttpRequest& request) {
	GURL absolute_url = embedded_test_server()->GetURL(request.relative_url);
	if (absolute_url.path() != "/test")
	return nullptr;

	std::unique_ptr<net::test_server::BasicHttpResponse> http_response(
	new net::test_server::BasicHttpResponse());
	http_response->set_code(net::HTTP_OK);
	http_response->set_content(kCanvasPageString);
	http_response->set_content_type("text/html");
	return http_response;
	}

	void WaitForAllWindowsToBeReady() {
	const std::u16string expected_title = u"Ready";
	// The subordinate windows may load asynchronously. Wait for all of
	// them to execute their script before proceeding.
	auto browser_list = Shell::windows();
	for (Shell* browser : browser_list) {
	TitleWatcher watcher(GetWebContents(browser), expected_title);
	const std::u16string& actual_title = watcher.WaitAndGetTitle();
	EXPECT_EQ(expected_title, actual_title);
	}
	}

	struct ExpectedColor {
	ExpectedColor() : r(0), g(0), b(0) {}
	bool operator==(const ExpectedColor& other) const {
	return (r == other.r && g == other.g && b == other.b);
	}
	uint8_t r;
	uint8_t g;
	uint8_t b;
	};

	void PickRandomColor(ExpectedColor* expected) {
	expected->r = static_cast<uint8_t>(base::RandInt(0, 256));
	expected->g = static_cast<uint8_t>(base::RandInt(0, 256));
	expected->b = static_cast<uint8_t>(base::RandInt(0, 256));
	}

	struct SerialSnapshot {
	SerialSnapshot() : host(nullptr) {}

	raw_ptr<content::RenderWidgetHost> host;
	ExpectedColor color;
	};
	std::vector<SerialSnapshot> expected_snapshots_;

	void SyncSnapshotCallback(content::RenderWidgetHostImpl* rwhi,
	const gfx::Image& image) {
	for (auto iter = expected_snapshots_.begin();
	iter != expected_snapshots_.end(); ++iter) {
	const SerialSnapshot& expected = *iter;
	if (expected.host == rwhi) {
	const SkBitmap* bitmap = image.ToSkBitmap();
	SkColor color = bitmap->getColor(1, 1);

	EXPECT_EQ(static_cast<int>(SkColorGetR(color)),
	static_cast<int>(expected.color.r))
	<< "Red channels differed";
	EXPECT_EQ(static_cast<int>(SkColorGetG(color)),
	static_cast<int>(expected.color.g))
	<< "Green channels differed";
	EXPECT_EQ(static_cast<int>(SkColorGetB(color)),
	static_cast<int>(expected.color.b))
	<< "Blue channels differed";

	expected_snapshots_.erase(iter);
	break;
	}
	}
	}

	std::map<content::RenderWidgetHost*, std::vector<ExpectedColor>>
	expected_async_snapshots_map_;
	int num_remaining_async_snapshots_ = 0;

	void AsyncSnapshotCallback(content::RenderWidgetHostImpl* rwhi,
	const gfx::Image& image) {
	--num_remaining_async_snapshots_;
	auto iterator = expected_async_snapshots_map_.find(rwhi);
	ASSERT_NE(iterator, expected_async_snapshots_map_.end());
	std::vector<ExpectedColor>& expected_snapshots = iterator->second;
	const SkBitmap* bitmap = image.ToSkBitmap();
	SkColor color = bitmap->getColor(1, 1);
	bool found = false;
	// Find first instance of this color in the list and clear out all
	// of the entries before that point. If it's not found, report
	// failure.
	for (auto iter = expected_snapshots.begin();
	iter != expected_snapshots.end(); ++iter) {
	const ExpectedColor& expected = *iter;
	if (SkColorGetR(color) == expected.r &&
	SkColorGetG(color) == expected.g &&
	SkColorGetB(color) == expected.b) {
	// Erase everything up to this color, but not this color
	// itself, since it might be returned again later on
	// subsequent snapshot requests.
	expected_snapshots.erase(expected_snapshots.begin(), iter);
	found = true;
	break;
	}
	}

	EXPECT_TRUE(found) << "Did not find color ("
	<< static_cast<int>(SkColorGetR(color)) << ", "
	<< static_cast<int>(SkColorGetG(color)) << ", "
	<< static_cast<int>(SkColorGetB(color))
	<< ") in expected snapshots for RWH 0x" << rwhi;
	}
	};

	// Even the single-window test doesn't work on Android yet. It's expected
	// that the multi-window tests would never work on that platform.
	#if !BUILDFLAG(IS_ANDROID)

	#if BUILDFLAG(IS_MAC)
	// TODO(crbug.com/40854618): This test is flakey on macOS.
	#define MAYBE_SingleWindowTest DISABLED_SingleWindowTest
	#else
	#define MAYBE_SingleWindowTest SingleWindowTest
	#endif
	IN_PROC_BROWSER_TEST_F(SnapshotBrowserTest, MAYBE_SingleWindowTest) {
	SetupTestServer();

	content::RenderWidgetHostImpl* rwhi = GetRenderWidgetHostImpl(shell());

	for (int i = 0; i < 40; ++i) {
	SerialSnapshot expected;
	expected.host = rwhi;
	PickRandomColor(&expected.color);

	std::string colorString = base::StringPrintf(
	"#%02x%02x%02x", expected.color.r, expected.color.g, expected.color.b);
	std::string script = std::string("fillWithColor(\"") + colorString + "\");";
	EXPECT_EQ(colorString, EvalJs(GetWebContents(shell()), script));

	expected_snapshots_.push_back(expected);

	// Get the snapshot from the surface rather than the window. The
	// on-screen display path is verified by the GPU tests, and it
	// seems difficult to figure out the colorspace transformation
	// required to make these color comparisons.
	rwhi->GetSnapshotFromBrowser(
	base::BindOnce(&SnapshotBrowserTest::SyncSnapshotCallback,
	base::Unretained(this), base::Unretained(rwhi)),
	true);
	while (expected_snapshots_.size() > 0) {
	base::RunLoop().RunUntilIdle();
	}
	}
	}

	// Timing out either all the time, or infrequently, apparently because
	// they're too slow, on the following configurations:
	// Windows Debug
	// Windows Release (https://crbug.com/1376441)
	// Linux Chromium OS ASAN LSAN Tests (1)
	// Linux TSAN Tests
	// See crbug.com/771119
	// TODO(crbug.com/40834774): Fix and enable on Fuchsia.
	#if BUILDFLAG(IS_WIN) \|\| BUILDFLAG(IS_CHROMEOS) \|\| BUILDFLAG(IS_FUCHSIA) \|\| \
	(BUILDFLAG(IS_LINUX) && defined(THREAD_SANITIZER))
	#define MAYBE_SyncMultiWindowTest DISABLED_SyncMultiWindowTest
	#else
	#define MAYBE_SyncMultiWindowTest SyncMultiWindowTest
	#endif
	IN_PROC_BROWSER_TEST_F(SnapshotBrowserTest, MAYBE_SyncMultiWindowTest) {
	SetupTestServer();

	for (int i = 0; i < 3; ++i) {
	EXPECT_EQ(true, EvalJs(GetWebContents(shell()), "openNewWindow()"));
	}

	base::RunLoop().RunUntilIdle();

	WaitForAllWindowsToBeReady();

	auto browser_list = Shell::windows();
	EXPECT_EQ(4u, browser_list.size());

	for (int i = 0; i < 20; ++i) {
	for (int j = 0; j < 4; j++) {
	// Start each iteration by taking a snapshot with a different
	// browser instance.
	int browser_index = (i + j) % 4;
	Shell* browser = browser_list[browser_index];
	content::RenderWidgetHostImpl* rwhi = GetRenderWidgetHostImpl(browser);

	SerialSnapshot expected;
	expected.host = rwhi;
	PickRandomColor(&expected.color);

	std::string colorString =
	base::StringPrintf("#%02x%02x%02x", expected.color.r,
	expected.color.g, expected.color.b);
	std::string script =
	std::string("fillWithColor(\"") + colorString + "\");";
	EXPECT_EQ(colorString, EvalJs(GetWebContents(browser), script));
	expected_snapshots_.push_back(expected);
	// Get the snapshot from the surface rather than the window. The
	// on-screen display path is verified by the GPU tests, and it
	// seems difficult to figure out the colorspace transformation
	// required to make these color comparisons.
	rwhi->GetSnapshotFromBrowser(
	base::BindOnce(&SnapshotBrowserTest::SyncSnapshotCallback,
	base::Unretained(this), base::Unretained(rwhi)),
	true);
	}

	while (expected_snapshots_.size() > 0) {
	base::RunLoop().RunUntilIdle();
	}
	}
	}

	// Timing out either all the time, or infrequently, apparently because
	// they're too slow, on the following configurations:
	// Windows Debug
	// Linux Chromium OS ASAN LSAN Tests (1)
	// Linux TSAN Tests
	// See crbug.com/771119
	// TODO(crbug.com/40740836): recently crashes flakily on
	// linux_chromium_asan_rel_ng and linux-rel.
	// TODO(crbug.com/40834774): Fix and enable on Fuchsia.
	#if (BUILDFLAG(IS_WIN) && !defined(NDEBUG)) \|\| BUILDFLAG(IS_CHROMEOS) \|\| \
	BUILDFLAG(IS_LINUX) \|\| BUILDFLAG(IS_FUCHSIA)
	#define MAYBE_AsyncMultiWindowTest DISABLED_AsyncMultiWindowTest
	#else
	#define MAYBE_AsyncMultiWindowTest AsyncMultiWindowTest
	#endif
	IN_PROC_BROWSER_TEST_F(SnapshotBrowserTest, MAYBE_AsyncMultiWindowTest) {
	SetupTestServer();

	for (int i = 0; i < 3; ++i) {
	EXPECT_EQ(true, EvalJs(GetWebContents(shell()), "openNewWindow()"));
	}

	base::RunLoop().RunUntilIdle();

	WaitForAllWindowsToBeReady();

	auto browser_list = Shell::windows();
	EXPECT_EQ(4u, browser_list.size());

	// This many pending snapshots per window will be put on the queue
	// before draining the requests. Anything more than 1 seems to catch
	// bugs which might otherwise be introduced in LatencyInfo's
	// propagation of the BROWSER_SNAPSHOT_FRAME_NUMBER_COMPONENT
	// component type.
	int divisor = 3;

	for (int i = 0; i < 10 * divisor; ++i) {
	for (int j = 0; j < 4; j++) {
	// Start each iteration by taking a snapshot with a different
	// browser instance.
	int browser_index = (i + j) % 4;
	Shell* browser = browser_list[browser_index];
	content::RenderWidgetHostImpl* rwhi = GetRenderWidgetHostImpl(browser);

	std::vector<ExpectedColor>& expected_snapshots =
	expected_async_snapshots_map_[rwhi];

	// Pick a unique random color.
	ExpectedColor expected;
	do {
	PickRandomColor(&expected);
	} while (base::Contains(expected_snapshots, expected));
	expected_snapshots.push_back(expected);

	std::string colorString = base::StringPrintf("#%02x%02x%02x", expected.r,
	expected.g, expected.b);
	std::string script =
	std::string("fillWithColor(\"") + colorString + "\");";
	EXPECT_EQ(colorString, EvalJs(GetWebContents(browser), script));
	// Get the snapshot from the surface rather than the window. The
	// on-screen display path is verified by the GPU tests, and it
	// seems difficult to figure out the colorspace transformation
	// required to make these color comparisons.
	rwhi->GetSnapshotFromBrowser(
	base::BindOnce(&SnapshotBrowserTest::AsyncSnapshotCallback,
	base::Unretained(this), base::Unretained(rwhi)),
	true);
	++num_remaining_async_snapshots_;
	}

	// Periodically yield and drain the async snapshot requests.
	if ((i % divisor) == 0) {
	bool drained;
	do {
	drained = true;
	for (auto iter = expected_async_snapshots_map_.begin();
	iter != expected_async_snapshots_map_.end(); ++iter) {
	if (iter->second.size() > 1) {
	drained = false;
	break;
	}
	}
	if (!drained) {
	base::RunLoop().RunUntilIdle();
	}
	} while (!drained);
	}
	}

	// At the end of the test, cooperatively wait for all of the snapshot
	// requests to be drained before exiting. This works around crashes
	// seen when tearing down the compositor while these requests are in
	// flight. Likely, user-visible APIs that use this facility are safe
	// in this regard.
	while (num_remaining_async_snapshots_ > 0) {
	base::RunLoop().RunUntilIdle();
	}
	}

	#endif // !BUILDFLAG(IS_ANDROID)

	} // namespace content