Calls ShortcutHelper::FinalizeLauncherIcon() on worker thread instead of on IO thread

chrome/browser/android/webapps/add_to_homescreen_data_fetcher.h

Index: chrome/browser/android/webapps/add_to_homescreen_data_fetcher.h
diff --git a/chrome/browser/android/webapps/add_to_homescreen_data_fetcher.h b/chrome/browser/android/webapps/add_to_homescreen_data_fetcher.h
index d02b94576e07aa3f981ee13c89db80f71d8d2554..ae3401bd3430859ff0612b8ad8d32d3362e4b743 100644
--- a/chrome/browser/android/webapps/add_to_homescreen_data_fetcher.h
+++ b/chrome/browser/android/webapps/add_to_homescreen_data_fetcher.h
@@ -44,9 +44,9 @@ class AddToHomescreenDataFetcher
     // Converts the icon into one that can be used on the Android Home screen.
     // |is_generated| is an out-param that indicates whether the icon was
     // generated by Chrome.
-    virtual SkBitmap FinalizeLauncherIcon(const SkBitmap& icon,
-                                          const GURL& url,
-                                          bool* is_generated) = 0;
+    virtual SkBitmap FinalizeLauncherIconInBackground(const SkBitmap& icon,
+                                                      const GURL& url,
+                                                      bool* is_generated) = 0;
 
     // Called when all the data needed to create a shortcut is available.
     virtual void OnDataAvailable(const ShortcutInfo& info,
@@ -92,7 +92,7 @@ class AddToHomescreenDataFetcher
       const favicon_base::FaviconRawBitmapResult& bitmap_result);
 
   // Creates the launcher icon from the given bitmap.
-  void CreateLauncherIcon(
+  void CreateLauncherIconInBackground(
       const favicon_base::FaviconRawBitmapResult& bitmap_result);
 
   // Callback run after an attempt to download manifest icon has been made. May