mojo: Fix Blink's shutdown sequence in AxProviderImplTest

components/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 "components/scheduler/renderer/renderer_scheduler_impl.h"
 
 #include "base/bind.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/trace_event_argument.h"
@@ skipping 20 matching lines @@
       compositor_task_runner_(
           helper_.TaskRunnerForQueue(COMPOSITOR_TASK_QUEUE)),
       loading_task_runner_(helper_.TaskRunnerForQueue(LOADING_TASK_QUEUE)),
       timer_task_runner_(helper_.TaskRunnerForQueue(TIMER_TASK_QUEUE)),
       delayed_update_policy_runner_(
           base::Bind(&RendererSchedulerImpl::UpdatePolicy,
                      base::Unretained(this)),
           helper_.ControlTaskRunner()),
       current_policy_(Policy::NORMAL),
       renderer_hidden_(false),
+      was_shutdown_(false),
       last_input_type_(blink::WebInputEvent::Undefined),
       input_stream_state_(InputStreamState::INACTIVE),
       policy_may_need_update_(&incoming_signals_lock_),
       timer_queue_suspend_count_(0),
       weak_factory_(this) {
   update_policy_closure_ = base::Bind(&RendererSchedulerImpl::UpdatePolicy,
                                       weak_factory_.GetWeakPtr());
   end_renderer_hidden_idle_period_closure_.Reset(base::Bind(
       &RendererSchedulerImpl::EndIdlePeriod, weak_factory_.GetWeakPtr()));
 
   for (size_t i = SchedulerHelper::TASK_QUEUE_COUNT; i < TASK_QUEUE_COUNT;
        i++) {
     helper_.SetQueueName(i, TaskQueueIdToString(static_cast<QueueId>(i)));
   }
   TRACE_EVENT_OBJECT_CREATED_WITH_ID(
       TRACE_DISABLED_BY_DEFAULT("renderer.scheduler"), "RendererScheduler",
       this);
 }
 
 RendererSchedulerImpl::~RendererSchedulerImpl() {
   TRACE_EVENT_OBJECT_DELETED_WITH_ID(
       TRACE_DISABLED_BY_DEFAULT("renderer.scheduler"), "RendererScheduler",
       this);
+  // Ensure the renderer scheduler was shut down explicitly, because otherwise
+  // we could end up having stale pointers to the Blink heap which has been
+  // terminated by this point.
+  DCHECK(was_shutdown_);
 }
 
 void RendererSchedulerImpl::Shutdown() {
   helper_.Shutdown();
+  was_shutdown_ = true;
 }
 
 scoped_refptr<base::SingleThreadTaskRunner>
 RendererSchedulerImpl::DefaultTaskRunner() {
   return helper_.DefaultTaskRunner();
 }
 
 scoped_refptr<base::SingleThreadTaskRunner>
 RendererSchedulerImpl::CompositorTaskRunner() {
   helper_.CheckOnValidThread();
@@ skipping 555 matching lines @@
       // meaningful touchstart response and should not impact task priority.
       return current_state;
 
     default:
       break;
   }
   return InputStreamState::ACTIVE;
 }
 
 }  // namespace scheduler