Introduce Zero Prefix URL Suggestions flag.

This flag controls support for Omnibox Zero Prefix URL Suggestions on Clank.
When enabled, Omnibox will start supplying suggestions for currently visited
website.

Bug: 934922
Change-Id: Ic28e81855198c5a21e1c0e2eeee02629f422ca1f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1516713
Reviewed-by: Filip Gorski <[email protected]>
Reviewed-by: Matthew Jones <[email protected]>
Reviewed-by: Mark Pearson <[email protected]>
Commit-Queue: Ender <[email protected]>
Cr-Commit-Position: refs/heads/master@{#641327}
diff --git a/components/omnibox/common/omnibox_features.cc b/components/omnibox/common/omnibox_features.cc
index 4b5325a..9486d34 100644
--- a/components/omnibox/common/omnibox_features.cc
+++ b/components/omnibox/common/omnibox_features.cc
@@ -273,4 +273,9 @@
 const base::Feature kOmniboxMaterialDesignWeatherIcons{
     "OmniboxMaterialDesignWeatherIcons", base::FEATURE_DISABLED_BY_DEFAULT};
 
+// Allow suggestions to be shown to the user on the New Tab Page upon focusing
+// URL bar (the omnibox).
+const base::Feature kZeroSuggestionsOnNTP{"OmniboxZeroSuggestionsOnNTP",
+                                          base::FEATURE_DISABLED_BY_DEFAULT};
+
 }  // namespace omnibox