De-dupe copy requests for tab capture in DelegatedFrameHost.

content/browser/renderer_host/render_widget_host_view_aura_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/browser/renderer_host/render_widget_host_view_aura.h"
 
 #include "base/basictypes.h"
 #include "base/command_line.h"
 #include "base/memory/shared_memory.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 2094 matching lines @@
   EXPECT_TRUE(view_->last_copy_request_);
   EXPECT_TRUE(view_->last_copy_request_->has_texture_mailbox());
   request = view_->last_copy_request_.Pass();
 
   // Send back the mailbox included in the request. There's no release callback
   // since the mailbox came from the RWHVA originally.
   request->SendTextureResult(view_rect.size(),
                              request->texture_mailbox(),
                              scoped_ptr<cc::SingleReleaseCallback>());
 
-  // This runs until the callback happens.
+  // Simulate a composite by running the loop and then notifying

[danakj, 2015/03/09 22:20:15]

Can you maybe add a test here that shows de-duping works?

[miu, 2015/03/10 02:50:43]

Done.

+  // DelegatedFrameHost that the graphics commands were issued.  The latter is
+  // required to clear the "frame subscriber de-duping" flag.
   run_loop.Run();
+  view_->GetDelegatedFrameHost()->OnCompositingStarted(nullptr,

[danakj, 2015/03/09 22:20:15]

Maybe you should OnCompositingEnded() here too, you know to match them.

[miu, 2015/03/10 02:50:43]

Done.

+                                                       base::TimeTicks::Now());
 
   // The callback should succeed.
   EXPECT_EQ(1, callback_count_);
   EXPECT_TRUE(result_);
 
   view_->OnSwapCompositorFrame(
       1, MakeDelegatedFrame(1.f, view_rect.size(), gfx::Rect(view_rect)));
 
   EXPECT_EQ(1, callback_count_);
   request = view_->last_copy_request_.Pass();
@@ skipping 1089 matching lines @@
   ui::TouchEvent press2(
       ui::ET_TOUCH_PRESSED, gfx::Point(20, 20), 1, ui::EventTimeForNow());
   view_->OnTouchEvent(&press2);
   SendInputEventACK(blink::WebInputEvent::TouchStart,
                     INPUT_EVENT_ACK_STATE_CONSUMED);
 
   EXPECT_EQ(2U, view_->dispatcher_->processed_touch_event_count());
 }
 
 }  // namespace content