Purge memory before suspending timer queues when backgrounded.

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

 // Copyright 2014 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 "platform/scheduler/renderer/renderer_scheduler_impl.h"
 
 #include "base/bind.h"
 #include "base/debug/stack_trace.h"
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/strings/stringprintf.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/trace_event_argument.h"
 #include "cc/output/begin_frame_args.h"
 #include "platform/scheduler/base/real_time_domain.h"
 #include "platform/scheduler/base/task_queue_impl.h"
 #include "platform/scheduler/base/task_queue_selector.h"
 #include "platform/scheduler/base/virtual_time_domain.h"
 #include "platform/scheduler/child/scheduler_tqm_delegate.h"
 #include "platform/scheduler/renderer/auto_advancing_virtual_time_domain.h"
 #include "platform/scheduler/renderer/task_queue_throttler.h"
 #include "platform/scheduler/renderer/web_view_scheduler_impl.h"
 #include "platform/scheduler/renderer/webthread_impl_for_renderer_scheduler.h"
+#include "public/platform/Platform.h"
 
 namespace blink {
 namespace scheduler {
 namespace {
 // The run time of loading tasks is strongly bimodal.  The vast majority are
 // very cheap, but there are usually a handful of very expensive tasks (e.g ~1
 // second on a mobile device) so we take a very pessimistic view when estimating
 // the cost of loading tasks.
 const int kLoadingTaskEstimationSampleCount = 1000;
 const double kLoadingTaskEstimationPercentile = 99;
@@ skipping 1528 matching lines @@
   UpdatePolicyLocked(UpdateType::MAY_EARLY_OUT_IF_POLICY_UNCHANGED);
 }
 
 void RendererSchedulerImpl::SuspendTimerQueueWhenBackgrounded() {
   DCHECK(MainThreadOnly().renderer_backgrounded);
   if (MainThreadOnly().timer_queue_suspended_when_backgrounded)
     return;
 
   MainThreadOnly().timer_queue_suspended_when_backgrounded = true;
   ForceUpdatePolicy();
+  Platform::current()->requestPurgeMemory();
 }
 
 void RendererSchedulerImpl::ResumeTimerQueueWhenForegroundedOrResumed() {
   DCHECK(!MainThreadOnly().renderer_backgrounded ||
          (MainThreadOnly().renderer_backgrounded &&
           !MainThreadOnly().renderer_suspended));
   if (!MainThreadOnly().timer_queue_suspended_when_backgrounded)
     return;
 
   MainThreadOnly().timer_queue_suspended_when_backgrounded = false;
@@ skipping 302 matching lines @@
     case TimeDomainType::VIRTUAL:
       return "virtual";
     default:
       NOTREACHED();
       return nullptr;
   }
 }
 
 }  // namespace scheduler
 }  // namespace blink