arc: Set custom icon in shelf for ARC apps.

chrome/browser/ui/app_list/arc/arc_app_icon.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_UI_APP_LIST_ARC_ARC_APP_ICON_H_
 #define CHROME_BROWSER_UI_APP_LIST_ARC_ARC_APP_ICON_H_
 
 #include <memory>
 #include <string>
 #include <vector>
@@ skipping 40 matching lines @@
   // done to avoid two problems. Problems come because icons are decoded at a
   // separate process created by ImageDecoder. ImageDecoder has 5 seconds delay
   // to stop since the last request (see its kBatchModeTimeoutSeconds for more
   // details). This is unacceptably long for unit tests because the test
   // framework waits until external process is finished. Another problem happens
   // when we issue a decoding request, but the process has not started its
   // processing yet by the time when a test exits. This might cause situation
   // when g_one_utility_thread_lock from in_process_utility_thread.cc gets
   // released in an acquired state which is crash condition in debug builds.
   static void DisableSafeDecodingForTesting();
+  static bool IsSafeDecodingDisabledForTesting();
 
  private:
   friend class ArcAppIconLoader;
   friend class ArcAppModelBuilder;
 
   class Source;
   class DecodeRequest;
   struct ReadResult;
 
   // Icon loading is performed in several steps. It is initiated by
@@ skipping 32 matching lines @@
 
   // Contains pending image decode requests.
   std::vector<std::unique_ptr<DecodeRequest>> decode_requests_;
 
   base::WeakPtrFactory<ArcAppIcon> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ArcAppIcon);
 };
 
 #endif  // CHROME_BROWSER_UI_APP_LIST_ARC_ARC_APP_ICON_H_