Expand web::BrowserState to add GetPath() method

Add a method to web::BrowserState returning the path where the
BrowserState data is stored.

BUG=429756

Committed: https://crrev.com/d537d6c355be1a51bbb808e9da214f5595d75f3d
Cr-Commit-Position: refs/heads/master@{#305191}

Review URL: https://codereview.chromium.org/740353002

Cr-Commit-Position: refs/heads/master@{#305199}
diff --git a/ios/web/public/browser_state.h b/ios/web/public/browser_state.h
index 47c398cd..f62ad94 100644
--- a/ios/web/public/browser_state.h
+++ b/ios/web/public/browser_state.h
@@ -7,6 +7,10 @@
 
 #include "base/supports_user_data.h"
 
+namespace base {
+class FilePath;
+}
+
 namespace net {
 class URLRequestContextGetter;
 }
@@ -20,9 +24,12 @@
  public:
   ~BrowserState() override;
 
-  // Return whether this BrowserState is incognito. Default is false.
+  // Returns whether this BrowserState is incognito. Default is false.
   virtual bool IsOffTheRecord() const = 0;
 
+  // Returns the path where the BrowserState data is stored.
+  virtual base::FilePath GetPath() const = 0;
+
   // Returns the request context information associated with this
   // BrowserState.
   virtual net::URLRequestContextGetter* GetRequestContext() = 0;