Fixing flakiness of TextureLayerChangeInvisibleMailboxTest

cc/trees/layer_tree_host_unittest.cc

 // Copyright 2011 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 "cc/trees/layer_tree_host.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 7484 matching lines @@
     DCHECK_EQ(hud->clip_tree_index(), root_layer->clip_tree_index());
     DCHECK_EQ(hud->effect_tree_index(), root_layer->effect_tree_index());
     DCHECK_EQ(hud->scroll_tree_index(), root_layer->scroll_tree_index());
   }
 
   void AfterTest() override {}
 };
 
 SINGLE_AND_MULTI_THREAD_TEST_F(LayerTreeHostTestHudLayerWithLayerLists);
 
+// Verifies that LayerTreeHost does not receive frame acks from a released

[danakj, 2017/04/18 20:58:42]

LayerTreeHostClient

[Saman Sami, 2017/04/18 21:37:13]

Done.

+// CompositorFrameSink.
+class LayerTreeHostTestDiscardAckAfterRelease : public LayerTreeHostTest {
+ protected:
+  void SetupTree() override {
+    scoped_refptr<Layer> root = Layer::Create();
+    root->SetBounds(gfx::Size(10, 10));
+    layer_tree_host()->SetRootLayer(root);

[danakj, 2017/04/18 20:58:42]

std::move()

[Saman Sami, 2017/04/18 21:37:13]

Done.

+    LayerTreeHostTest::SetupTree();
+  }
+
+  void BeginTest() override { PostSetNeedsCommitToMainThread(); }
+
+  void WillReceiveCompositorFrameAckOnImplThread() override {
+    MainThreadTaskRunner()->PostTask(
+        FROM_HERE, base::Bind(&LayerTreeHostTestDiscardAckAfterRelease::
+                                  ReleaseCompositorFrameSink,
+                              base::Unretained(this)));
+  }
+
+  void DidReceiveCompositorFrameAckOnImplThread() override {
+    MainThreadTaskRunner()->PostTask(
+        FROM_HERE,
+        base::Bind(
+            &LayerTreeHostTestDiscardAckAfterRelease::VerifyAckNotReceived,

[danakj, 2017/04/18 20:58:42]

Can you post the VerifyAckNotReceived with a small delay (100ms?). Not because
what you have is racey but just in case code changes in the future, and the ack
ends up going down a different path, maybe gets posted later, then the test
would see the ack happen /at least/ flakily.

[Saman Sami, 2017/04/18 21:37:13]

Done. Good point.

+            base::Unretained(this)));
+  }
+
+  void DidReceiveCompositorFrameAck() override { received_ack_ = true; }
+
+  void ReleaseCompositorFrameSink() {
+    layer_tree_host()->SetVisible(false);
+    layer_tree_host()->ReleaseCompositorFrameSink();
+  }
+
+  void VerifyAckNotReceived() {
+    EXPECT_FALSE(received_ack_);
+    EndTest();
+  }
+
+  void AfterTest() override {}
+
+ private:
+  bool received_ack_ = false;
+};
+
+SINGLE_AND_MULTI_THREAD_TEST_F(LayerTreeHostTestDiscardAckAfterRelease);
+
 }  // namespace
 }  // namespace cc