MSE: Implement SourceBuffer.trackDefaults

Source/modules/mediasource/SourceBuffer.cpp

Index: Source/modules/mediasource/SourceBuffer.cpp
diff --git a/Source/modules/mediasource/SourceBuffer.cpp b/Source/modules/mediasource/SourceBuffer.cpp
index e44acdd05d626cece4f1c5cec1854f1354e93d36..d8572d8dd93e390f1cf37aa8e2e79cc17009a15f 100644
--- a/Source/modules/mediasource/SourceBuffer.cpp
+++ b/Source/modules/mediasource/SourceBuffer.cpp
@@ -83,6 +83,7 @@ SourceBuffer::SourceBuffer(PassOwnPtr<WebSourceBuffer> webSourceBuffer, MediaSou
     : ActiveDOMObject(source->executionContext())
     , m_webSourceBuffer(webSourceBuffer)
     , m_source(source)
+    , m_trackDefaults(TrackDefaultList::create())

[haraken, 2014/12/16 01:16:16]

Do we need to create an empty vector? Can we just use nullptr?

[sof, 2014/12/16 07:24:36]

Don't think the IDL allows for that in practice, an empty TrackListDefault
should be returned.

[philipj_slow, 2014/12/16 09:55:48]

Right, that is the topic of the spec bug Matthew filed:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=27599

     , m_asyncEventQueue(asyncEventQueue)
     , m_mode(segmentsKeyword())
     , m_updating(false)
@@ -366,6 +367,22 @@ void SourceBuffer::remove(double start, double end, ExceptionState& exceptionSta
     m_removeAsyncPartRunner.runAsync();
 }
 
+void SourceBuffer::setTrackDefaults(TrackDefaultList* trackDefaults, ExceptionState& exceptionState)
+{
+    // Per 02 Dec 2014 Editor's Draft
+    // http://w3c.github.io/media-source/#widl-SourceBuffer-trackDefaults
+    // 1. If this object has been removed from the sourceBuffers attribute of
+    //    the parent media source, then throw an InvalidStateError exception
+    //    and abort these steps.
+    // 2. If the updating attribute equals true, then throw an InvalidStateError
+    //    exception and abort these steps.
+    if (throwExceptionIfRemovedOrUpdating(isRemoved(), m_updating, exceptionState))
+        return;
+
+    // 3. Update the attribute to the new value.
+    m_trackDefaults = trackDefaults;
+}
+
 void SourceBuffer::abortIfUpdating()
 {
     // Section 3.2 abort() method step 3 substeps.
@@ -746,6 +763,7 @@ void SourceBuffer::trace(Visitor* visitor)
 {
     visitor->trace(m_source);
     visitor->trace(m_stream);
+    visitor->trace(m_trackDefaults);
     visitor->trace(m_asyncEventQueue);
     EventTargetWithInlineData::trace(visitor);
 }