Don't request missing favicon on every page request.

android_webview/browser/icon_helper.h

Index: android_webview/browser/icon_helper.h
diff --git a/android_webview/browser/icon_helper.h b/android_webview/browser/icon_helper.h
index e684cdf569674b9685f45d0b005a7198c387fbef..390ac39113b0e6d194790bb4af19c2a895b8912f 100644
--- a/android_webview/browser/icon_helper.h
+++ b/android_webview/browser/icon_helper.h
@@ -37,8 +37,9 @@ class IconHelper : public content::WebContentsObserver {
   virtual void DidUpdateFaviconURL(int32 page_id,
       const std::vector<content::FaviconURL>& candidates) OVERRIDE;
 
-  void DownloadFaviconCallback(int id, const GURL& image_url,
-      int requested_size, const std::vector<SkBitmap>& bitmaps);
+  void DownloadFaviconCallback(int id, int http_status_code,
+      const GURL& image_url, int requested_size,
+      const std::vector<SkBitmap>& bitmaps);
 
  private:
   Listener* listener_;