Prepare for WebContentLayerClient API change

ui/compositor/layer.h

 // Copyright (c) 2012 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 UI_COMPOSITOR_LAYER_H_
 #define UI_COMPOSITOR_LAYER_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 211 matching lines @@
   // Returns true if the layer scales its content.
   bool scale_content() const { return scale_content_; }
 
   // Sometimes the Layer is being updated by something other than SetCanvas
   // (e.g. the GPU process on UI_COMPOSITOR_IMAGE_TRANSPORT).
   bool layer_updated_externally() const { return layer_updated_externally_; }
 
   // WebContentLayerClient
   virtual void paintContents(WebKit::WebCanvas*,
                              const WebKit::WebRect& clip,
+#if defined(WEBCONTENTLAYERCLIENT_FLOAT_OPAQUE_RECT)
+                             WebKit::WebFloatRect& opaque);
+#else
                              WebKit::WebRect& opaque);
+#endif
 
   WebKit::WebLayer web_layer() { return web_layer_; }
 
   float device_scale_factor() const { return device_scale_factor_; }
 
   // Forces a render surface to be used on this layer. This has no positive
   // impact, and is only used for benchmarking/testing purpose.
   void SetForceRenderSurface(bool force);
   bool force_render_surface() const { return force_render_surface_; }
 
@@ skipping 99 matching lines @@
 
   // A cached copy of |Compositor::device_scale_factor()|.
   float device_scale_factor_;
 
   DISALLOW_COPY_AND_ASSIGN(Layer);
 };
 
 }  // namespace ui
 
 #endif  // UI_COMPOSITOR_LAYER_H_