(Merge m52) Fix a bug with throttling and timer queue suspension

components/scheduler/renderer/throttling_helper_unittest.cc

 // Copyright 2015 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 "components/scheduler/renderer/throttling_helper.h"
 
 #include <stddef.h>
 
 #include <memory>
 
@@ skipping 353 matching lines @@
   timer_queue_->PostTask(FROM_HERE, base::Bind(&NopTask));
 
   EXPECT_TRUE(timer_queue_->IsQueueEnabled());
   throttling_helper_->IncreaseThrottleRefCount(timer_queue_.get());
   EXPECT_FALSE(timer_queue_->IsQueueEnabled());
 
   mock_task_runner_->RunUntilIdle();  // Wait until the pump.
   EXPECT_TRUE(timer_queue_->IsQueueEnabled());
 }
 
-TEST_F(ThrottlingHelperTest, TaskQueueEnabledOnUnthrottle) {
+TEST_F(ThrottlingHelperTest, TaskQueueUnthrottle_InitiallyEnabled) {
   timer_queue_->PostTask(FROM_HERE, base::Bind(&NopTask));
 
+  timer_queue_->SetQueueEnabled(true);  // NOP
   throttling_helper_->IncreaseThrottleRefCount(timer_queue_.get());
   EXPECT_FALSE(timer_queue_->IsQueueEnabled());
 
   throttling_helper_->DecreaseThrottleRefCount(timer_queue_.get());
   EXPECT_TRUE(timer_queue_->IsQueueEnabled());
 }
 
+TEST_F(ThrottlingHelperTest, TaskQueueUnthrottle_InitiallyDisabled) {
+  timer_queue_->PostTask(FROM_HERE, base::Bind(&NopTask));
+
+  timer_queue_->SetQueueEnabled(false);
+  throttling_helper_->IncreaseThrottleRefCount(timer_queue_.get());
+  EXPECT_FALSE(timer_queue_->IsQueueEnabled());
+
+  throttling_helper_->DecreaseThrottleRefCount(timer_queue_.get());
+  EXPECT_FALSE(timer_queue_->IsQueueEnabled());
+}
+
+TEST_F(ThrottlingHelperTest, SetQueueEnabled_Unthrottled) {
+  timer_queue_->PostTask(FROM_HERE, base::Bind(&NopTask));
+
+  throttling_helper_->SetQueueEnabled(timer_queue_.get(), false);
+  EXPECT_FALSE(timer_queue_->IsQueueEnabled());
+
+  throttling_helper_->SetQueueEnabled(timer_queue_.get(), true);
+  EXPECT_TRUE(timer_queue_->IsQueueEnabled());
+}
+
+TEST_F(ThrottlingHelperTest, SetQueueEnabled_DisabledWhileThrottled) {
+  timer_queue_->PostTask(FROM_HERE, base::Bind(&NopTask));
+
+  throttling_helper_->IncreaseThrottleRefCount(timer_queue_.get());
+  EXPECT_FALSE(timer_queue_->IsQueueEnabled());
+
+  throttling_helper_->SetQueueEnabled(timer_queue_.get(), false);
+  throttling_helper_->DecreaseThrottleRefCount(timer_queue_.get());
+  EXPECT_FALSE(timer_queue_->IsQueueEnabled());
+}
+
+TEST_F(ThrottlingHelperTest, TaskQueueDisabledTillPump_ThenManuallyDisabled) {
+  timer_queue_->PostTask(FROM_HERE, base::Bind(&NopTask));
+
+  EXPECT_TRUE(timer_queue_->IsQueueEnabled());
+  throttling_helper_->IncreaseThrottleRefCount(timer_queue_.get());
+  EXPECT_FALSE(timer_queue_->IsQueueEnabled());
+
+  mock_task_runner_->RunUntilIdle();  // Wait until the pump.
+  EXPECT_TRUE(timer_queue_->IsQueueEnabled());
+
+  throttling_helper_->SetQueueEnabled(timer_queue_.get(), false);
+  EXPECT_FALSE(timer_queue_->IsQueueEnabled());
+}
+
 }  // namespace scheduler