Allow WebExternalTextureLayers to receive a bitmap along with a mailbox

cc/layers/texture_layer.h

 // Copyright 2010 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 CC_LAYERS_TEXTURE_LAYER_H_
 #define CC_LAYERS_TEXTURE_LAYER_H_
 
 #include <string>
 
 #include "base/callback.h"
@@ skipping 49 matching lines @@
 
   // Code path for plugins which supply their own texture ID.
   void SetTextureId(unsigned texture_id);
 
   // Code path for plugins which supply their own mailbox.
   bool uses_mailbox() const { return uses_mailbox_; }
   void SetTextureMailbox(const TextureMailbox& mailbox);
 
   void WillModifyTexture();
 
+  // Returns true if the layer must use a mailbox with shared memory or an
+  // SkBitmap.
+  bool MustUseBitmap();
+
   virtual void SetNeedsDisplayRect(const gfx::RectF& dirty_rect) OVERRIDE;
 
   virtual void SetLayerTreeHost(LayerTreeHost* layer_tree_host) OVERRIDE;
   virtual bool DrawsContent() const OVERRIDE;
   virtual void Update(ResourceUpdateQueue* queue,
                       const OcclusionTracker* occlusion,
                       RenderingStats* stats) OVERRIDE;
   virtual void PushPropertiesTo(LayerImpl* layer) OVERRIDE;
   virtual bool BlocksPendingCommit() const OVERRIDE;
 
@@ skipping 36 matching lines @@
 
   unsigned texture_id_;
   scoped_refptr<MailboxHolder> holder_;
   bool needs_set_mailbox_;
 
   DISALLOW_COPY_AND_ASSIGN(TextureLayer);
 };
 
 }  // namespace cc
 #endif  // CC_LAYERS_TEXTURE_LAYER_H_