Use a struct for cc::Surface ids for more type safety

content/common/cc_messages_unittest.cc

 // 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.
 
 #include "content/common/cc_messages.h"
 
 #include <string.h>
 
 #include <algorithm>
 
@@ skipping 385 matching lines @@
   streamvideo_in->SetAll(shared_state3_in,
                          arbitrary_rect2,
                          arbitrary_rect2_inside_rect2,
                          arbitrary_rect1_inside_rect2,
                          arbitrary_bool1,
                          arbitrary_resourceid2,
                          arbitrary_matrix);
   scoped_ptr<DrawQuad> streamvideo_cmp = streamvideo_in->Copy(
       streamvideo_in->shared_quad_state);
 
-  int arbitrary_surface_id = 3;
+  cc::SurfaceId arbitrary_surface_id;
+  arbitrary_surface_id.id = 3;
   scoped_ptr<SurfaceDrawQuad> surface_in = SurfaceDrawQuad::Create();
   surface_in->SetAll(shared_state3_in,
                      arbitrary_rect2,
                      arbitrary_rect2_inside_rect2,
                      arbitrary_rect1_inside_rect2,
                      arbitrary_bool1,
                      arbitrary_surface_id);
   scoped_ptr<DrawQuad> surface_cmp = surface_in->Copy(
       surface_in->shared_quad_state);
 
@@ skipping 391 matching lines @@
     SoftwareFrameData frame_out;
     PickleIterator iter(msg);
     EXPECT_EQ(
         expect_read,
         IPC::ParamTraits<SoftwareFrameData>::Read(&msg, &iter, &frame_out));
   }
 }
 
 }  // namespace
 }  // namespace content