Moved theme related state from BrowserInstantController to InstantService.

chrome/browser/search/instant_service.h

Index: chrome/browser/search/instant_service.h
diff --git a/chrome/browser/search/instant_service.h b/chrome/browser/search/instant_service.h
index 4832dedc21ef65289c1739bd4138519831b228e5..a6d4aa28996f7dcc6088842da67f8cf99f9ac8ff 100644
--- a/chrome/browser/search/instant_service.h
+++ b/chrome/browser/search/instant_service.h
@@ -14,6 +14,7 @@
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
+#include "base/observer_list.h"
 #include "chrome/browser/history/history_types.h"
 #include "chrome/common/instant_types.h"
 #include "components/browser_context_keyed_service/browser_context_keyed_service.h"
@@ -22,7 +23,9 @@
 
 class GURL;
 class InstantIOContext;
+class InstantServiceObserver;
 class Profile;
+class ThemeService;
 
 namespace net {
 class URLRequest;
@@ -40,6 +43,10 @@ class InstantService : public BrowserContextKeyedService,
   void AddInstantProcess(int process_id);
   bool IsInstantProcess(int process_id) const;
 
+  // Adds/Removes InstantService observers.
+  void AddObserver(InstantServiceObserver* observer);
+  void RemoveObserver(InstantServiceObserver* observer);
+
 #if defined(UNIT_TEST)
   int GetInstantProcessCount() const {
     return process_ids_.size();
@@ -64,6 +71,9 @@ class InstantService : public BrowserContextKeyedService,
   void GetCurrentMostVisitedItems(
       std::vector<InstantMostVisitedItem>* items) const;
 
+  // Invoked by the InstantController to update theme information for NTP.
+  void UpdateThemeInfo();

[samarth, 2013/06/19 05:34:54]

TODO: calling this from InstantController really shouldn't be necessary.  We
should investigate if it is and why (but this can wait).

[kmadhusu, 2013/06/19 17:43:30]

Added TODO.

+
  private:
   // Overridden from BrowserContextKeyedService:
   virtual void Shutdown() OVERRIDE;
@@ -78,6 +88,9 @@ class InstantService : public BrowserContextKeyedService,
   // SendMostVisitedItems.
   void OnMostVisitedItemsReceived(const history::MostVisitedURLList& data);
 
+  // Theme changed notification handler.
+  void OnThemeChanged(ThemeService* theme_service);
+
   Profile* const profile_;
 
   // The process ids associated with Instant processes.
@@ -86,6 +99,11 @@ class InstantService : public BrowserContextKeyedService,
   // InstantMostVisitedItems sent to the Instant Pages.
   std::vector<InstantMostVisitedItem> most_visited_items_;
 
+  // Theme-related data for NTP overlay to adopt themes.
+  ThemeBackgroundInfo theme_info_;
+
+  ObserverList<InstantServiceObserver> observers_;
+
   content::NotificationRegistrar registrar_;
 
   scoped_refptr<InstantIOContext> instant_io_context_;