Add lock around modification of HostSharedBitmapManagerClient::owned_bitmaps_

content/common/host_shared_bitmap_manager.h

 // Copyright (c) 2013 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 CONTENT_COMMON_HOST_SHARED_BITMAP_MANAGER_H_
 #define CONTENT_COMMON_HOST_SHARED_BITMAP_MANAGER_H_
 
 #include <map>
 #include <set>
 
@@ skipping 33 matching lines @@
       const cc::SharedBitmapId& id,
       base::SharedMemoryHandle* shared_memory_handle);
   void ChildAllocatedSharedBitmap(size_t buffer_size,
                                   const base::SharedMemoryHandle& handle,
                                   base::ProcessHandle process_handle,
                                   const cc::SharedBitmapId& id);
   void ChildDeletedSharedBitmap(const cc::SharedBitmapId& id);
 
  private:
   HostSharedBitmapManager* manager_;
+  base::Lock lock_;
   base::hash_set<cc::SharedBitmapId> owned_bitmaps_;
 
   DISALLOW_COPY_AND_ASSIGN(HostSharedBitmapManagerClient);
 };
 
 class CONTENT_EXPORT HostSharedBitmapManager
     : public cc::SharedBitmapManager,
       public base::trace_event::MemoryDumpProvider {
  public:
   HostSharedBitmapManager();
@@ skipping 35 matching lines @@
   typedef base::hash_map<cc::SharedBitmapId, scoped_refptr<BitmapData> >
       BitmapMap;
   BitmapMap handle_map_;
 
   DISALLOW_COPY_AND_ASSIGN(HostSharedBitmapManager);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_HOST_SHARED_BITMAP_MANAGER_H_