cc : Enable LayerTreeHostTestGpuRasterDeviceSizeChanged test

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 00d1ee8c553a73259c90e0e7e98b44c4f05c10f0..ae4f6349bfab59b4beafb9c27b30996da8e5f648 100644
--- a/cc/trees/layer_tree_host_unittest.cc
+++ b/cc/trees/layer_tree_host_unittest.cc
@@ -1511,13 +1511,6 @@ class LayerTreeHostTestGpuRasterDeviceSizeChanged : public LayerTreeHostTest {
     settings->gpu_rasterization_forced = true;
   }
 
-  void DrawLayersOnThread(LayerTreeHostImpl* impl) override {
-    if (num_draws_ < 2) {
-      PostSetNeedsRedrawRectToMainThread(invalid_rect_);
-      num_draws_++;
-    }
-  }
-
   void CommitCompleteOnThread(LayerTreeHostImpl* host_impl) override {
     if (num_draws_ == 2) {
       auto* pending_tree = host_impl->pending_tree();
@@ -1537,8 +1530,8 @@ class LayerTreeHostTestGpuRasterDeviceSizeChanged : public LayerTreeHostTest {
       EXPECT_EQ(
           pending_tiling->TilingDataForTesting().max_texture_size().width(),
           active_tiling->TilingDataForTesting().max_texture_size().width());
-      EndTest();
     }
+    PostSetNeedsCommitToMainThread();

[danakj, 2016/09/29 21:35:53]

one nit: you could just put this as layer_tree_host()->SetNeedsCommit() in
DidCommitAndDrawFrame. Less posting = less chances for confusion with ordering.

[jaydasika, 2016/09/30 00:20:52]

Done.

   }
 
   void DidCommitAndDrawFrame() override {
@@ -1546,6 +1539,10 @@ class LayerTreeHostTestGpuRasterDeviceSizeChanged : public LayerTreeHostTest {
     if (num_draws_ == 1) {
       layer_tree()->SetViewportSize(gfx::Size(400, 64));
     }
+    if (num_draws_ == 2)
+      EndTest();
+    PostSetNeedsRedrawRectToMainThread(invalid_rect_);

[danakj, 2016/09/29 21:35:53]

this doesn't need to post, it can just set the redraw rect on layer_tree_host()
directly since this is the main thread.

Also, don't do this if we're ending/ended test. So like

if (num_draws_ < 2) {
  lth->SetNeedsRedrawRect
  lth->SetNeedsCommit
} else {
  EndTest();
}

?

[jaydasika, 2016/09/30 00:20:52]

Done.

+    num_draws_++;
   }
 
   void AfterTest() override {}
@@ -1560,8 +1557,7 @@ class LayerTreeHostTestGpuRasterDeviceSizeChanged : public LayerTreeHostTest {
 
 // As there's no pending tree in single-threaded case, this test should run
 // only for multi-threaded case.
-// Disabled because its timing out flakily. crbug.com/598491
-// MULTI_THREAD_TEST_F(LayerTreeHostTestGpuRasterDeviceSizeChanged);
+MULTI_THREAD_TEST_F(LayerTreeHostTestGpuRasterDeviceSizeChanged);
 
 class LayerTreeHostTestNoExtraCommitFromInvalidate : public LayerTreeHostTest {
  public: