sync compositor: pass simple gfx types by const ref

content/browser/android/in_process/synchronous_compositor_impl.cc

 // Copyright 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.
 
 #include "content/browser/android/in_process/synchronous_compositor_impl.h"
 
 #include "base/auto_reset.h"
 #include "base/bind.h"
 #include "base/lazy_instance.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 156 matching lines @@
       nullptr);
 
   synchronous_input_handler_proxy_ = nullptr;
   begin_frame_source_ = nullptr;
   output_surface_ = nullptr;
   // Don't propogate this signal from one renderer to the next.
   need_animate_input_ = false;
 }
 
 scoped_ptr<cc::CompositorFrame> SynchronousCompositorImpl::DemandDrawHw(
-    gfx::Size surface_size,
+    const gfx::Size& surface_size,
     const gfx::Transform& transform,
-    gfx::Rect viewport,
-    gfx::Rect clip,
-    gfx::Rect viewport_rect_for_tile_priority,
+    const gfx::Rect& viewport,
+    const gfx::Rect& clip,
+    const gfx::Rect& viewport_rect_for_tile_priority,
     const gfx::Transform& transform_for_tile_priority) {
   DCHECK(CalledOnValidThread());
   DCHECK(output_surface_);
   DCHECK(begin_frame_source_);
 
   scoped_ptr<cc::CompositorFrame> frame =
       output_surface_->DemandDrawHw(surface_size,
                                     transform,
                                     viewport,
                                     clip,
@@ skipping 180 matching lines @@
   DCHECK(contents);
   DCHECK(client);
   g_factory.Get();  // Ensure it's initialized.
   WebContentsAndroid* web_contents_android =
       static_cast<WebContentsImpl*>(contents)->GetWebContentsAndroid();
   DCHECK(!web_contents_android->synchronous_compositor_client());
   web_contents_android->set_synchronous_compositor_client(client);
 }
 
 }  // namespace content