Use per-frame WebTaskRunner with makeCancellable in AXObjectCacheImpl

third_party/WebKit/Source/modules/accessibility/AXObjectCacheImpl.cpp

Index: third_party/WebKit/Source/modules/accessibility/AXObjectCacheImpl.cpp
diff --git a/third_party/WebKit/Source/modules/accessibility/AXObjectCacheImpl.cpp b/third_party/WebKit/Source/modules/accessibility/AXObjectCacheImpl.cpp
index 7df53a74a50a9c87e7d258b1f3cf56d67559efcf..888e84dd5168ef31483ea398fcac1602706063dd 100644
--- a/third_party/WebKit/Source/modules/accessibility/AXObjectCacheImpl.cpp
+++ b/third_party/WebKit/Source/modules/accessibility/AXObjectCacheImpl.cpp
@@ -31,6 +31,7 @@
 #include "core/HTMLNames.h"
 #include "core/InputTypeNames.h"
 #include "core/dom/Document.h"
+#include "core/dom/TaskRunnerHelper.h"
 #include "core/editing/EditingUtilities.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
@@ -97,7 +98,6 @@ AXObjectCacheImpl::AXObjectCacheImpl(Document& document)
 #if ENABLE(ASSERT)
     , m_hasBeenDisposed(false)
 #endif
-    , m_notificationPostTimer(this, &AXObjectCacheImpl::notificationPostTimerFired)
 {
 }
 
@@ -108,7 +108,7 @@ AXObjectCacheImpl::~AXObjectCacheImpl()
 
 void AXObjectCacheImpl::dispose()
 {
-    m_notificationPostTimer.stop();
+    m_notificationPostCanceller.cancel();
 
     for (auto& entry : m_objects) {
         AXObject* obj = entry.value;
@@ -648,10 +648,8 @@ void AXObjectCacheImpl::childrenChanged(AXObject* obj)
     obj->childrenChanged();
 }
 
-void AXObjectCacheImpl::notificationPostTimerFired(TimerBase*)
+void AXObjectCacheImpl::postNotificationsNow()
 {
-    m_notificationPostTimer.stop();
-
     unsigned i = 0, count = m_notificationsToPost.size();
     for (i = 0; i < count; ++i) {
         AXObject* obj = m_notificationsToPost[i].first;
@@ -708,8 +706,12 @@ void AXObjectCacheImpl::postNotification(AXObject* object, AXNotification notifi
         return;
 
     m_notificationsToPost.append(std::make_pair(object, notification));
-    if (!m_notificationPostTimer.isActive())
-        m_notificationPostTimer.startOneShot(0, BLINK_FROM_HERE);
+    if (m_notificationPostCanceller.isActive())
+        return;
+
+    auto result = WTF::makeCancellable(WTF::bind(&AXObjectCacheImpl::postNotificationsNow, wrapWeakPersistent(this)));
+    m_notificationPostCanceller = std::move(result.canceller);
+    TaskRunnerHelper::get(TaskType::Internal, m_document)->postTask(BLINK_FROM_HERE, std::move(result.function));
 }
 
 bool AXObjectCacheImpl::isAriaOwned(const AXObject* child) const