InstantExtended: Prevent spurious themechanged/mostvisitedchanged events

chrome/common/instant_types.h

Index: chrome/common/instant_types.h
diff --git a/chrome/common/instant_types.h b/chrome/common/instant_types.h
index 07f4eb457b5dce288f283f5e19f208fd2ae46a6b..20b29b677ba67cd72a3bfe7c1cb6dac3af2032e9 100644
--- a/chrome/common/instant_types.h
+++ b/chrome/common/instant_types.h
@@ -123,6 +123,8 @@ enum ThemeBackgroundImageTiling {
   THEME_BKGRND_IMAGE_REPEAT,
 };
 
+// Update IsThemeInfoEqual in chrome/renderer/searchbox/searchbox.cc
+// whenever any fields are added/removed.
 struct ThemeBackgroundInfo {
   ThemeBackgroundInfo();
   ~ThemeBackgroundInfo();
@@ -158,6 +160,8 @@ struct ThemeBackgroundInfo {
   bool has_attribution;
 };
 
+// Update AreMostVisitedItemsEqual in chrome/renderer/searchbox/searchbox.cc
+// whenever any fields are added/removed.
 struct InstantMostVisitedItem {
   // The URL of the Most Visited item.
   GURL url;