Refactor client visibility handling

cc/output/context_cache_controller_unittest.cc

+// Copyright (c) 2016 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/output/context_cache_controller.h"
+
+#include "base/memory/ptr_util.h"
+#include "cc/test/test_context_provider.h"
+#include "cc/test/test_context_support.h"
+#include "cc/test/test_web_graphics_context_3d.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace cc {
+namespace {
+using ::testing::Mock;
+using ::testing::StrictMock;
+
+class MockContextSupport : public TestContextSupport {
+ public:
+  MockContextSupport() {}
+  MOCK_METHOD1(SetAggressivelyFreeResources,
+               void(bool aggressively_free_resources));
+};
+
+TEST(ContextCacheControllerTest, ScopedVisibilityBasic) {
+  StrictMock<MockContextSupport> context_support;
+  ContextCacheController cache_controller(&context_support);
+
+  EXPECT_CALL(context_support, SetAggressivelyFreeResources(false));
+  auto visibility = cache_controller.ClientBecameVisible();

[danakj, 2016/08/26 23:49:08]

the type of |visiblity| is not actually mentioned anywhere, and we're not simply
using it as a temp var. so maybe you should spell out the name of it

[ericrk, 2016/08/29 22:43:22]

sure - but it's sooo long :P

+  Mock::VerifyAndClearExpectations(&context_support);
+
+  EXPECT_CALL(context_support, SetAggressivelyFreeResources(true));
+  cache_controller.ClientBecameNotVisible(std::move(visibility));
+}
+
+TEST(ContextCacheControllerTest, ScopedVisibilityMulti) {
+  StrictMock<MockContextSupport> context_support;
+  ContextCacheController cache_controller(&context_support);
+
+  EXPECT_CALL(context_support, SetAggressivelyFreeResources(false));
+  auto visibility_1 = cache_controller.ClientBecameVisible();
+  Mock::VerifyAndClearExpectations(&context_support);
+  auto visibility_2 = cache_controller.ClientBecameVisible();
+
+  cache_controller.ClientBecameNotVisible(std::move(visibility_1));
+  EXPECT_CALL(context_support, SetAggressivelyFreeResources(true));
+  cache_controller.ClientBecameNotVisible(std::move(visibility_2));
+}
+
+}  // namespace
+}  // namespace cc