cc: Setup API to release OutputSurface from LTHClient.

cc/trees/layer_tree_host_unittest_context.cc

Index: cc/trees/layer_tree_host_unittest_context.cc
diff --git a/cc/trees/layer_tree_host_unittest_context.cc b/cc/trees/layer_tree_host_unittest_context.cc
index 7c766fe8bedc60376fafb543e8f51667e2c40682..14829221e1e865361c67f95906467dd5cde75f95 100644
--- a/cc/trees/layer_tree_host_unittest_context.cc
+++ b/cc/trees/layer_tree_host_unittest_context.cc
@@ -382,6 +382,66 @@ class LayerTreeHostClientNotReadyDoesNotCreateOutputSurface
 SINGLE_AND_MULTI_THREAD_TEST_F(
     LayerTreeHostClientNotReadyDoesNotCreateOutputSurface);
 
+class LayerTreeHostClientTakeAwayOutputSurface
+    : public LayerTreeHostContextTest {
+ public:
+  LayerTreeHostClientTakeAwayOutputSurface()
+      : LayerTreeHostContextTest(), setos_counter_(0), made_visible_(false) {}
+
+  void BeginTest() override { PostSetNeedsCommitToMainThread(); }
+
+  void RequestNewOutputSurface() override {
+    if (!made_visible_)

[no sievers, 2015/09/11 22:44:50]

You mean 'if (made_visible_)'? Or you could simply do 'if
(layer_tree_host()->visible()'.

It's supposed to test the following use case (and it would be nice to put that
in a comment above the class here:

// SetUp LTH and create and init OutputSurface
// LTH::SetVisible(false);
// LTH::ReleaseOutputSurface();
// ...
// LTH::SetVisible(true);
// Create and init new OutputSurface

[sohanjg, 2015/09/14 13:01:27]

Done.

+      CreateAndSetOutputSurface();
+  }
+
+  void CreateAndSetOutputSurface() {
+    scoped_ptr<OutputSurface> surface =
+        LayerTreeHostContextTest::CreateOutputSurface();
+    CHECK(surface);
+    layer_tree_host()->SetOutputSurface(surface.Pass());
+    setos_counter_++;
+  }
+
+  void HideAndReleaseOutputSurface() {
+    EXPECT_TRUE(layer_tree_host()->proxy()->IsMainThread());
+    layer_tree_host()->SetVisible(false);
+    made_visible_ = false;
+    scoped_ptr<OutputSurface> surface =
+        layer_tree_host()->ReleaseOutputSurface();
+    CHECK(surface);
+    MainThreadTaskRunner()->PostTask(
+        FROM_HERE,
+        base::Bind(&LayerTreeHostClientTakeAwayOutputSurface::MakeVisible,
+                   base::Unretained(this)));
+  }
+
+  void DidInitializeOutputSurface() override {
+    if (setos_counter_ == 0) {

[no sievers, 2015/09/11 22:44:50]

== 1? Otherwise this is unreachable, and it probably explains how your test
passed with the inverted condition in line 394.

[sohanjg, 2015/09/14 13:01:27]

Done.

+      EXPECT_TRUE(layer_tree_host()->visible());
+      MainThreadTaskRunner()->PostTask(
+          FROM_HERE, base::Bind(&LayerTreeHostClientTakeAwayOutputSurface::
+                                    HideAndReleaseOutputSurface,
+                                base::Unretained(this)));
+    } else {
+      EndTest();
+    }
+  }
+
+  void MakeVisible() {
+    EXPECT_TRUE(layer_tree_host()->proxy()->IsMainThread());
+    layer_tree_host()->SetVisible(true);
+    made_visible_ = true;
+  }
+
+  void AfterTest() override {}
+
+  int setos_counter_;
+  bool made_visible_;
+};
+
+SINGLE_AND_MULTI_THREAD_TEST_F(LayerTreeHostClientTakeAwayOutputSurface);
+
 class MultipleCompositeDoesNotCreateOutputSurface
     : public LayerTreeHostContextTest {
  public: