Enable StopNonTimersInBackground by default on Android.

Bug: 822954
Change-Id: Ife5a6460c0215fa188e3734fa781ecfb994e94b9
Reviewed-on: https://chromium-review.googlesource.com/1241994
Commit-Queue: Shubhie Panicker <panicker@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Reviewed-by: Alexander Timin <altimin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#594148}

third_party/blink/common/features.cc

@@ -67,10 +67,16 @@ const base::Feature kStopInBackground {
 #endif
 };
 
-// Freeze non-timer task queues in background, after allowed grace time. Launch
-// bug: https://crbug.com/822954. "stop" is a legacy name.
-const base::Feature kStopNonTimersInBackground{
-    "stop-non-timers-in-background", base::FEATURE_DISABLED_BY_DEFAULT};
+// Freeze non-timer task queues in background, after allowed grace time.
+// "stop" is a legacy name.
+const base::Feature kStopNonTimersInBackground {
+  "stop-non-timers-in-background",
+#if defined(OS_ANDROID)
+      base::FEATURE_ENABLED_BY_DEFAULT
+#else
+      base::FEATURE_DISABLED_BY_DEFAULT
+#endif
+};
 
 // Writable files and native filesystem access. https://crbug.com/853326
 const base::Feature kWritableFilesAPI{"WritableFilesAPI",

third_party/blink/renderer/platform/scheduler/main_thread/frame_scheduler_impl_unittest.cc

@@ -160,6 +160,14 @@ class FrameSchedulerImplStopNonTimersInBackgroundEnabledTest
                                {}) {}
 };
 
+class FrameSchedulerImplStopNonTimersInBackgroundDisabledTest
+    : public FrameSchedulerImplTest {
+ public:
+  FrameSchedulerImplStopNonTimersInBackgroundDisabledTest()
+      : FrameSchedulerImplTest({},
+                               {blink::features::kStopNonTimersInBackground}) {}
+};
+
 namespace {
 
 class MockLifecycleObserver final : public FrameScheduler::Observer {
@@ -391,7 +399,8 @@ TEST_F(FrameSchedulerImplStopNonTimersInBackgroundEnabledTest,
   EXPECT_EQ(5, counter);
 }
 
-TEST_F(FrameSchedulerImplTest, PageFreezeAndUnfreezeFlagDisabled) {
+TEST_F(FrameSchedulerImplStopNonTimersInBackgroundDisabledTest,
+       PageFreezeAndUnfreezeFlagDisabled) {
   int counter = 0;
   LoadingTaskQueue()->task_runner()->PostTask(
       FROM_HERE, base::BindOnce(&IncrementCounter, base::Unretained(&counter)));
@@ -1612,6 +1621,8 @@ class ThrottleableAndFreezableTaskTypesTest
 };
 
 TEST_F(ThrottleableAndFreezableTaskTypesTest, QueueTraitsFromFieldTrialParams) {
+  if (base::FeatureList::IsEnabled(blink::features::kStopNonTimersInBackground))
+    return;
   // These tests will start to fail if the default task queues or queue traits
   // change for these task types.
 
@@ -1627,7 +1638,6 @@ TEST_F(ThrottleableAndFreezableTaskTypesTest, QueueTraitsFromFieldTrialParams) {
       task_queue->GetQueueTraits(),
       MainThreadTaskQueue::QueueTraits().SetCanBeFrozen(true).SetCanBePaused(
           true));
-
   task_queue = GetTaskQueue(TaskType::kDatabaseAccess);
   EXPECT_EQ(task_queue->GetQueueTraits(), MainThreadTaskQueue::QueueTraits()
                                               .SetCanBeThrottled(true)
@@ -1669,6 +1679,9 @@ class FreezableOnlyTaskTypesTest
 };
 
 TEST_F(FreezableOnlyTaskTypesTest, QueueTraitsFromFieldTrialParams) {
+  if (base::FeatureList::IsEnabled(blink::features::kStopNonTimersInBackground))
+    return;
+
   // These tests will start to fail if the default task queues or queue traits
   // change for these task types.
 
@@ -1726,6 +1739,9 @@ class ThrottleableOnlyTaskTypesTest
 };
 
 TEST_F(ThrottleableOnlyTaskTypesTest, QueueTraitsFromFieldTrialParams) {
+  if (base::FeatureList::IsEnabled(blink::features::kStopNonTimersInBackground))
+    return;
+
   // These tests will start to fail if the default task queues or queue traits
   // change for these task types.