[Presentation API] fire onconnectionavailable and onconnect event asynchronously

third_party/WebKit/Source/modules/presentation/PresentationConnection.cpp

Index: third_party/WebKit/Source/modules/presentation/PresentationConnection.cpp
diff --git a/third_party/WebKit/Source/modules/presentation/PresentationConnection.cpp b/third_party/WebKit/Source/modules/presentation/PresentationConnection.cpp
index e7d005333b686f332fb64a173e789ece4d5ca05e..d85c78ed3295bd55e32292428f45aaa5aa47ac23 100644
--- a/third_party/WebKit/Source/modules/presentation/PresentationConnection.cpp
+++ b/third_party/WebKit/Source/modules/presentation/PresentationConnection.cpp
@@ -9,6 +9,7 @@
 #include "core/dom/DOMArrayBufferView.h"
 #include "core/dom/Document.h"
 #include "core/dom/ExceptionCode.h"
+#include "core/dom/ExecutionContextTask.h"
 #include "core/events/Event.h"
 #include "core/events/MessageEvent.h"
 #include "core/fileapi/FileReaderLoader.h"
@@ -191,9 +192,11 @@ PresentationConnection* PresentationConnection::take(
   PresentationConnection* connection = new PresentationConnection(
       controller->frame(), client->getId(), client->getUrl());
   controller->registerConnection(connection);
-  request->dispatchEvent(PresentationConnectionAvailableEvent::create(
-      EventTypeNames::connectionavailable, connection));
-
+  request->getExecutionContext()->postTask(
+      BLINK_FROM_HERE,
+      createSameThreadTask(
+          &PresentationRequest::dispatchConnectionAvailableEvent,
+          wrapPersistent(request), wrapPersistent(connection)));
   return connection;
 }
 
@@ -415,10 +418,10 @@ void PresentationConnection::didChangeState(
       NOTREACHED();
       return;
     case WebPresentationConnectionState::Connected:
-      dispatchEvent(Event::create(EventTypeNames::connect));
+      dispatchEventAsync(Event::create(EventTypeNames::connect));
       return;
     case WebPresentationConnectionState::Terminated:
-      dispatchEvent(Event::create(EventTypeNames::terminate));
+      dispatchEventAsync(Event::create(EventTypeNames::terminate));
       return;
     // Closed state is handled in |didClose()|.
     case WebPresentationConnectionState::Closed:
@@ -435,7 +438,7 @@ void PresentationConnection::didClose(
     return;
 
   m_state = WebPresentationConnectionState::Closed;
-  dispatchEvent(PresentationConnectionCloseEvent::create(
+  dispatchEventAsync(PresentationConnectionCloseEvent::create(
       EventTypeNames::close, connectionCloseReasonToString(reason), message));
 }
 
@@ -464,6 +467,17 @@ void PresentationConnection::didFailLoadingBlob(
   handleMessageQueue();
 }
 
+void PresentationConnection::dispatchEventAsync(Event* event) {

[mark a. foltz, 2016/12/07 04:23:55]

Can this be combined into dispatchStateChangeEvent?

[zhaobin, 2016/12/07 19:30:43]

Not sure how to combine them neatly. postTask expects void return type, while
dispatchEvent returns DispatchEventResult. We need some function wrapper to
convert return type.

[mark a. foltz, 2016/12/07 21:32:44]

Ah, got it.  Slight preference to call this method dispatchStateChangeEvent and
to name the method below dispatchEventAsync.

It would also be possible to write a static utility function void
dispatchEventAsync(EventTarget*, Event*) to be used with PostTask here and above
for connectionavailable, but I don't feel strongly.

[zhaobin, 2016/12/08 00:16:46]

Done.

+  getExecutionContext()->postTask(
+      BLINK_FROM_HERE,
+      createSameThreadTask(&PresentationConnection::dispatchStateChangeEvent,
+                           wrapPersistent(this), wrapPersistent(event)));
+}
+
+void PresentationConnection::dispatchStateChangeEvent(Event* event) {
+  dispatchEvent(event);
+}
+
 void PresentationConnection::tearDown() {
   // Cancel current Blob loading if any.
   if (m_blobLoader) {