Implement DTMF [[ToneBuffer]] in the blink layer

This CL makes the Blink layer keep a copy of the tone buffer
and update it on insertDTMF and ontonechange events only; this
makes it possible to expose the state of the tone buffer at the
time the event is fired to the Javascript callback.

It removes a queueing step inside the DTMF sender, because
that queueing step destroyed the consistency.

Bug: chromium:816475
Change-Id: I5aa68396299a67d6cea1e8a17d364f553514c291
Reviewed-on: https://chromium-review.googlesource.com/1213084Reviewed-by: Guido Urdaneta <guidou@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Harald Alvestrand <hta@chromium.org>
Cr-Commit-Position: refs/heads/master@{#589910}

content/renderer/media/webrtc/rtc_dtmf_sender_handler.cc

@@ -30,18 +30,20 @@ class RtcDtmfSenderHandler::Observer :
 
   ~Observer() override {}
 
-  void OnToneChange(const std::string& tone) override {
+  void OnToneChange(const std::string& tone,
+                    const std::string& tone_buffer) override {
     main_thread_->PostTask(
         FROM_HERE,
         base::BindOnce(
             &RtcDtmfSenderHandler::Observer::OnToneChangeOnMainThread, this,
-            tone));
+            tone, tone_buffer));
   }
 
-  void OnToneChangeOnMainThread(const std::string& tone) {
+  void OnToneChangeOnMainThread(const std::string& tone,
+                                const std::string& tone_buffer) {
     DCHECK(thread_checker_.CalledOnValidThread());
     if (handler_)
-      handler_->OnToneChange(tone);
+      handler_->OnToneChange(tone, tone_buffer);
   }
 
   base::ThreadChecker thread_checker_;
@@ -85,12 +87,14 @@ bool RtcDtmfSenderHandler::InsertDTMF(const blink::WebString& tones,
                                   static_cast<int>(interToneGap));
 }
 
-void RtcDtmfSenderHandler::OnToneChange(const std::string& tone) {
+void RtcDtmfSenderHandler::OnToneChange(const std::string& tone,
+                                        const std::string& tone_buffer) {
   if (!webkit_client_) {
     LOG(ERROR) << "WebRTCDTMFSenderHandlerClient not set.";
     return;
   }
-  webkit_client_->DidPlayTone(blink::WebString::FromUTF8(tone));
+  webkit_client_->DidPlayTone(blink::WebString::FromUTF8(tone),
+                              blink::WebString::FromUTF8(tone_buffer));
 }
 
 }  // namespace content

content/renderer/media/webrtc/rtc_dtmf_sender_handler.h

@@ -38,7 +38,7 @@ class CONTENT_EXPORT RtcDtmfSenderHandler
                   long duration,
                   long interToneGap) override;
 
-  void OnToneChange(const std::string& tone);
+  void OnToneChange(const std::string& tone, const std::string& tone_buffer);
 
  private:
   scoped_refptr<webrtc::DtmfSenderInterface> dtmf_sender_;

third_party/WebKit/LayoutTests/TestExpectations

@@ -4605,8 +4605,6 @@ crbug.com/806249 virtual/video-surface-layer/external/wpt/html/semantics/embedde
 crbug.com/806249 virtual/video-surface-layer/external/wpt/html/semantics/embedded-content/media-elements/autoplay-default-feature-policy.https.sub.html [ Skip ]
 crbug.com/806249 virtual/video-surface-layer/external/wpt/html/semantics/embedded-content/media-elements/autoplay-disabled-by-feature-policy.https.sub.html [ Skip ]
 
-# Sheriff 2018-02-26
-crbug.com/816475 [ Win7 Linux ] external/wpt/webrtc/RTCDTMFSender-ontonechange.https.html [ Failure Pass ]
 crbug.com/816914 [ Mac ] fast/canvas/canvas-drawImage-live-video.html [ Failure Pass ]
 crbug.com/817167 http/tests/devtools/oopif/oopif-cookies-refresh.js [ Failure Timeout Pass ]
 
@@ -4700,8 +4698,6 @@ crbug.com/840881 virtual/service-worker-servicification/external/wpt/service-wor
 crbug.com/831993 [ Linux ] virtual/gpu-rasterization/images/cross-fade-overflow-position.html [ Pass Timeout ]
 
 # Sheriff 2018-04-13
-crbug.com/832842 [ Win7 Linux ] virtual/webrtc-wpt-unified-plan/external/wpt/webrtc/RTCDTMFSender-ontonechange.https.html [ Failure ]
-crbug.com/832842 [ Mac ] virtual/webrtc-wpt-unified-plan/external/wpt/webrtc/RTCDTMFSender-ontonechange.https.html [ Failure Pass ]
 crbug.com/833655 [ Linux ] media/controls/closed-captions-dynamic-update.html [ Skip ]
 crbug.com/833655 [ Linux ] virtual/new-remote-playback-pipeline/media/controls/closed-captions-dynamic-update.html [ Skip ]
 crbug.com/833655 [ Linux ] virtual/video-surface-layer/media/controls/closed-captions-dynamic-update.html [ Skip ]

third_party/WebKit/LayoutTests/external/wpt/webrtc/RTCDTMFSender-helper.js

@@ -109,7 +109,7 @@ function test_tone_change_events(testFunc, toneChanges, desc) {
         const now = Date.now();
         const duration = now - lastEventTime;
 
-        assert_approx_equals(duration, expectedDuration, 250,
+        assert_approx_equals(duration, expectedDuration, 400,
           `Expect tonechange event for "${tone}" to be fired approximately after ${expectedDuration} milliseconds`);
 
         lastEventTime = now;

third_party/blink/public/platform/web_rtc_dtmf_sender_handler_client.h

@@ -36,7 +36,8 @@ class WebRTCDTMFSenderHandlerClient {
  public:
   virtual ~WebRTCDTMFSenderHandlerClient() = default;
 
-  virtual void DidPlayTone(const WebString& tone) = 0;
+  virtual void DidPlayTone(const WebString& tone,
+                           const WebString& tone_buffer) = 0;
 };
 
 }  // namespace blink

third_party/blink/renderer/modules/peerconnection/rtc_dtmf_sender.cc

@@ -58,10 +58,7 @@ RTCDTMFSender::RTCDTMFSender(ExecutionContext* context,
                              std::unique_ptr<WebRTCDTMFSenderHandler> handler)
     : ContextLifecycleObserver(context),
       handler_(std::move(handler)),
-      stopped_(false),
-      scheduled_event_timer_(context->GetTaskRunner(TaskType::kNetworking),
-                             this,
-                             &RTCDTMFSender::ScheduledEventTimerFired) {
+      stopped_(false) {
   handler_->SetClient(this);
 }
 
@@ -79,7 +76,7 @@ bool RTCDTMFSender::canInsertDTMF() const {
 }
 
 String RTCDTMFSender::toneBuffer() const {
-  return handler_->CurrentToneBuffer();
+  return tone_buffer_;
 }
 
 void RTCDTMFSender::insertDTMF(const String& tones,
@@ -129,10 +126,14 @@ void RTCDTMFSender::insertDTMF(const String& tones,
         "Could not send provided tones, '" + tones + "'.");
     return;
   }
+  tone_buffer_ = handler_->CurrentToneBuffer();
 }
 
-void RTCDTMFSender::DidPlayTone(const WebString& tone) {
-  ScheduleDispatchEvent(RTCDTMFToneChangeEvent::Create(tone));
+void RTCDTMFSender::DidPlayTone(const WebString& tone,
+                                const WebString& tone_buffer) {
+  tone_buffer_ = tone_buffer;
+  Member<Event> event = RTCDTMFToneChangeEvent::Create(tone);
+  DispatchEvent(*event.Release());
 }
 
 const AtomicString& RTCDTMFSender::InterfaceName() const {
@@ -148,27 +149,7 @@ void RTCDTMFSender::ContextDestroyed(ExecutionContext*) {
   handler_->SetClient(nullptr);
 }
 
-void RTCDTMFSender::ScheduleDispatchEvent(Event* event) {
-  scheduled_events_.push_back(event);
-
-  if (!scheduled_event_timer_.IsActive())
-    scheduled_event_timer_.StartOneShot(TimeDelta(), FROM_HERE);
-}
-
-void RTCDTMFSender::ScheduledEventTimerFired(TimerBase*) {
-  if (stopped_)
-    return;
-
-  HeapVector<Member<Event>> events;
-  events.swap(scheduled_events_);
-
-  HeapVector<Member<Event>>::iterator it = events.begin();
-  for (; it != events.end(); ++it)
-    DispatchEvent(*it->Release());
-}
-
 void RTCDTMFSender::Trace(blink::Visitor* visitor) {
-  visitor->Trace(scheduled_events_);
   EventTargetWithInlineData::Trace(visitor);
   ContextLifecycleObserver::Trace(visitor);
 }

third_party/blink/renderer/modules/peerconnection/rtc_dtmf_sender.h

@@ -75,18 +75,14 @@ class RTCDTMFSender final : public EventTargetWithInlineData,
                 std::unique_ptr<WebRTCDTMFSenderHandler>);
   void Dispose();
 
-  void ScheduleDispatchEvent(Event*);
-  void ScheduledEventTimerFired(TimerBase*);
-
   // WebRTCDTMFSenderHandlerClient
-  void DidPlayTone(const WebString&) override;
+  void DidPlayTone(const WebString& tone,
+                   const WebString& tone_buffer) override;
 
   std::unique_ptr<WebRTCDTMFSenderHandler> handler_;
 
   bool stopped_;
-
-  TaskRunnerTimer<RTCDTMFSender> scheduled_event_timer_;
-  HeapVector<Member<Event>> scheduled_events_;
+  String tone_buffer_;
 };
 
 }  // namespace blink