[Presentation API] Added the DefaultPresentationStart event and parsing of the default presentation…

Source/modules/presentation/Presentation.cpp

Index: Source/modules/presentation/Presentation.cpp
diff --git a/Source/modules/presentation/Presentation.cpp b/Source/modules/presentation/Presentation.cpp
index 6213d4f13505572dec88ee06057941372f2fe0df..f8c23793164f8ce08199999066bb62ba88d28ff9 100644
--- a/Source/modules/presentation/Presentation.cpp
+++ b/Source/modules/presentation/Presentation.cpp
@@ -14,11 +14,32 @@
 #include "core/frame/LocalFrame.h"
 #include "modules/EventTargetModules.h"
 #include "modules/presentation/AvailableChangeEvent.h"
+#include "modules/presentation/DefaultPresentationStartEvent.h"
 #include "modules/presentation/PresentationController.h"
 #include "modules/presentation/PresentationSessionClientCallbacks.h"
 
 namespace blink {
 
+struct PresentationEventInfo {
+    using EventWatcherUpdateFunc = void (PresentationController::*)(bool);
+
+    AtomicString eventType;
+    EventWatcherUpdateFunc updateFunc;
+};
+
+// Maps the event type to the corresponding update method of PresentationController.
+static PresentationEventInfo* presentationEventInfos(unsigned& length)

[Peter Beverloo, 2015/03/03 21:19:25]

nit: unsigned int? Not strictly required (yet), but closer to Chromium style.

[whywhat, 2015/03/05 18:41:47]

Removed

+{
+    static PresentationEventInfo eventInfos[] = {
+        { EventTypeNames::availablechange, &PresentationController::updateAvailableChangeWatched },

[Peter Beverloo, 2015/03/03 21:19:25]

You're introducing a static initializer here.

PresentationEventInfo.eventType should be a const&.

[whywhat, 2015/03/05 18:41:47]

Acknowledged.

+        { EventTypeNames::defaultpresentationstart, &PresentationController::updateDefaultPresentationStartWatched },

[Peter Beverloo, 2015/03/03 21:19:25]

How many events do you expect to have in the end? It's hard to make a judgement
call about whether to prefer some duplicated code or this array structure
without that data. Perhaps there'd be an opportunity to generalize code in some
other way?

[whywhat, 2015/03/05 18:41:47]

Acknowledged.

+    };
+    length = WTF_ARRAY_LENGTH(eventInfos);
+
+    return eventInfos;
+}
+
+

[Peter Beverloo, 2015/03/03 21:19:25]

nit: double blank line

[whywhat, 2015/03/05 18:41:47]

Done.

 Presentation::Presentation(LocalFrame* frame)
     : DOMWindowProperty(frame)
 {
@@ -95,44 +116,74 @@ ScriptPromise Presentation::joinSession(ScriptState* state, const String& presen
 
 bool Presentation::addEventListener(const AtomicString& eventType, PassRefPtr<EventListener> listener, bool useCapture)
 {
-    bool hadEventListeners = hasEventListeners(EventTypeNames::availablechange);
-    if (!RefCountedGarbageCollectedEventTargetWithInlineData<Presentation>::addEventListener(eventType, listener, useCapture))
-        return false;
+    unsigned length = 0;
+    PresentationEventInfo* eventInfos = presentationEventInfos(length);

[Peter Beverloo, 2015/03/03 21:19:24]

nit: may as well pass a pointer to presentationEventInfo for readability. Not
strictly required by the styleguide.

[whywhat, 2015/03/05 18:41:47]

Acknowledged.

 
-    if (hasEventListeners(EventTypeNames::availablechange) && !hadEventListeners) {
-        PresentationController* controller = presentationController();
-        if (controller)
-            controller->updateAvailableChangeWatched(true);
+    for (unsigned i = 0; i < length; ++i) {
+        PresentationEventInfo& eventInfo = eventInfos[i];
+        if (eventInfo.eventType != eventType)
+            continue;
+
+        bool hadEventListeners = hasEventListeners(eventType);
+        if (!RefCountedGarbageCollectedEventTargetWithInlineData<Presentation>::addEventListener(eventType, listener, useCapture))
+            return false;
+
+        if (hasEventListeners(eventType) && !hadEventListeners) {
+            PresentationController* controller = presentationController();
+            if (controller)
+                (controller->*eventInfo.updateFunc)(true);
+        }
+
+        return true;
     }
 
-    return true;
+    return RefCountedGarbageCollectedEventTargetWithInlineData<Presentation>::addEventListener(eventType, listener, useCapture);
 }
 
 bool Presentation::removeEventListener(const AtomicString& eventType, PassRefPtr<EventListener> listener, bool useCapture)
 {
-    bool hadEventListeners = hasEventListeners(EventTypeNames::availablechange);
-    if (!RefCountedGarbageCollectedEventTargetWithInlineData<Presentation>::removeEventListener(eventType, listener, useCapture))
-        return false;
+    unsigned length = 0;
+    PresentationEventInfo* eventInfos = presentationEventInfos(length);
 
-    if (hadEventListeners && !hasEventListeners(EventTypeNames::availablechange)) {
-        PresentationController* controller = presentationController();
-        if (controller)
-            controller->updateAvailableChangeWatched(false);
+    for (unsigned i = 0; i < length; ++i) {
+        PresentationEventInfo& eventInfo = eventInfos[i];
+        if (eventInfo.eventType != eventType)
+            continue;
+
+        bool hadEventListeners = hasEventListeners(eventType);
+        if (!RefCountedGarbageCollectedEventTargetWithInlineData<Presentation>::removeEventListener(eventType, listener, useCapture))
+            return false;
+
+        if (hadEventListeners && !hasEventListeners(eventType)) {
+            PresentationController* controller = presentationController();
+            if (controller)
+                (controller->*eventInfo.updateFunc)(false);
+        }
+
+        return true;
     }
 
-    return true;
+    return RefCountedGarbageCollectedEventTargetWithInlineData<Presentation>::removeEventListener(eventType, listener, useCapture);
 }
 
 void Presentation::removeAllEventListeners()
 {
-    bool hadEventListeners = hasEventListeners(EventTypeNames::availablechange);
-    RefCountedGarbageCollectedEventTargetWithInlineData<Presentation>::removeAllEventListeners();
+    unsigned length = 0;
+    PresentationEventInfo* eventInfos = presentationEventInfos(length);
+
+    for (unsigned i = 0; i < length; ++i) {
+        PresentationEventInfo& eventInfo = eventInfos[i];
+        if (!hasEventListeners(eventInfo.eventType))
+            continue;
 
-    if (hadEventListeners) {
         PresentationController* controller = presentationController();
-        if (controller)
-            controller->updateAvailableChangeWatched(false);
+        if (!controller)
+            continue;
+
+        (controller->*eventInfo.updateFunc)(false);
     }
+
+    RefCountedGarbageCollectedEventTargetWithInlineData<Presentation>::removeAllEventListeners();
 }
 
 void Presentation::didChangeAvailability(bool available)
@@ -145,6 +196,16 @@ bool Presentation::isAvailableChangeWatched() const
     return hasEventListeners(EventTypeNames::availablechange);
 }
 
+void Presentation::didStartDefaultPresentation(PresentationSession* session)
+{
+    dispatchEvent(DefaultPresentationStartEvent::create(EventTypeNames::defaultpresentationstart, session));
+}
+
+bool Presentation::isDefaultPresentationStartWatched() const
+{
+    return hasEventListeners(EventTypeNames::defaultpresentationstart);
+}
+
 void Presentation::registerSession(PresentationSession* session)
 {
     m_openSessions.add(session);