Fixing flakiness of TextureLayerChangeInvisibleMailboxTest

cc/trees/layer_tree_host_unittest.cc

Index: cc/trees/layer_tree_host_unittest.cc
diff --git a/cc/trees/layer_tree_host_unittest.cc b/cc/trees/layer_tree_host_unittest.cc
index 2e7457a49aac6600be861bf479eb244c545a3d17..2c4563c1e02dd69015e91d8d05a314a8fde04d74 100644
--- a/cc/trees/layer_tree_host_unittest.cc
+++ b/cc/trees/layer_tree_host_unittest.cc
@@ -7502,5 +7502,53 @@ class LayerTreeHostTestHudLayerWithLayerLists : public LayerTreeHostTest {
 
 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