[scheduler] Fix TaskQueueThrottler::SetQueueEnabled logic.

third_party/WebKit/Source/platform/scheduler/renderer/task_queue_throttler_unittest.cc

Index: third_party/WebKit/Source/platform/scheduler/renderer/task_queue_throttler_unittest.cc
diff --git a/third_party/WebKit/Source/platform/scheduler/renderer/task_queue_throttler_unittest.cc b/third_party/WebKit/Source/platform/scheduler/renderer/task_queue_throttler_unittest.cc
index 47bcf16d4f9201630fe49ac1ba2e61383fc45a9d..c14645cf95ce22b3b5262cb3d193ffdb55e6be5c 100644
--- a/third_party/WebKit/Source/platform/scheduler/renderer/task_queue_throttler_unittest.cc
+++ b/third_party/WebKit/Source/platform/scheduler/renderer/task_queue_throttler_unittest.cc
@@ -992,5 +992,28 @@ TEST_F(TaskQueueThrottlerTest, GrantAdditionalBudget) {
   pool->Close();
 }
 
+TEST_F(TaskQueueThrottlerTest,
+       TaskQueueThrottledAndDisabledTillPump_ThenManuallyEnabled) {
+  size_t count = 0;
+  timer_queue_->PostTask(FROM_HERE, base::Bind(&AddOneTask, &count));
+
+  EXPECT_TRUE(timer_queue_->IsQueueEnabled());
+  task_queue_throttler_->IncreaseThrottleRefCount(timer_queue_.get());
+  EXPECT_FALSE(timer_queue_->IsQueueEnabled());
+
+  task_queue_throttler_->SetQueueEnabled(timer_queue_.get(), false);
+  EXPECT_FALSE(timer_queue_->IsQueueEnabled());
+
+  mock_task_runner_->RunUntilIdle();
+  EXPECT_EQ(0u, count);
+
+  task_queue_throttler_->SetQueueEnabled(timer_queue_.get(), true);
+  EXPECT_FALSE(timer_queue_->IsQueueEnabled());
+
+  mock_task_runner_->RunUntilIdle();  // Wait until the pump.
+  EXPECT_EQ(1u, count);               // Task ran
+  EXPECT_TRUE(timer_queue_->IsQueueEnabled());
+}
+
 }  // namespace scheduler
 }  // namespace blink