Moved theme related state from BrowserInstantController to InstantService.

chrome/browser/ui/search/search_tab_helper.cc

Index: chrome/browser/ui/search/search_tab_helper.cc
diff --git a/chrome/browser/ui/search/search_tab_helper.cc b/chrome/browser/ui/search/search_tab_helper.cc
index 4cbbd8aa2dfe33e1049e180d742d98c106842fdc..9dfbb81c9907cb9658ad88071ad22ccdffaa8b13 100644
--- a/chrome/browser/ui/search/search_tab_helper.cc
+++ b/chrome/browser/ui/search/search_tab_helper.cc
@@ -84,6 +84,15 @@ bool SearchTabHelper::UpdateLastKnownMostVisitedItems(
   return true;
 }
 
+bool SearchTabHelper::UpdateLastKnownThemeBackgroundInfo(
+    const ThemeBackgroundInfo& theme_info) {
+  if (last_known_theme_info_ == theme_info)
+    return false;
+
+  last_known_theme_info_ = theme_info;
+  return true;
+}
+
 void SearchTabHelper::Observe(
     int type,
     const content::NotificationSource& source,
@@ -91,6 +100,7 @@ void SearchTabHelper::Observe(
   DCHECK_EQ(content::NOTIFICATION_NAV_ENTRY_COMMITTED, type);
   UpdateMode();
   last_known_most_visited_items_.clear();
+  last_known_theme_info_ = ThemeBackgroundInfo();
 }
 
 bool SearchTabHelper::OnMessageReceived(const IPC::Message& message) {