Omnibox UI Experiments: Add feature flags for 3 URL elision experiments.

chrome/browser/flag_descriptions.h

Index: chrome/browser/flag_descriptions.h
diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
index 070dcceab3ae4801c5513921aa61b9f454ae3638..34649e6c9ac47c491e13ebbe48f5e481559b2f78 100644
--- a/chrome/browser/flag_descriptions.h
+++ b/chrome/browser/flag_descriptions.h
@@ -501,6 +501,15 @@ extern const char kOffMainThreadFetchDescription[];
 extern const char kOmniboxDisplayTitleForCurrentUrlName[];
 extern const char kOmniboxDisplayTitleForCurrentUrlDescription[];
 
+extern const char kOmniboxUIHideSuggestionUrlPathName[];
+extern const char kOmniboxUIHideSuggestionUrlPathDescription[];
+
+extern const char kOmniboxUIHideSuggestionUrlSchemeName[];
+extern const char kOmniboxUIHideSuggestionUrlSchemeDescription[];
+
+extern const char kOmniboxUIHideSuggestionUrlTrivialSubdomainsName[];
+extern const char kOmniboxUIHideSuggestionUrlTrivialSubdomainsDescription[];
+
 extern const char kOmniboxUIMaxAutocompleteMatchesName[];
 extern const char kOmniboxUIMaxAutocompleteMatchesDescription[];