MSE: Start letting SourceBuffer begin to do initialization segment received algorithm

Source/modules/mediasource/MediaSource.cpp

Index: Source/modules/mediasource/MediaSource.cpp
diff --git a/Source/modules/mediasource/MediaSource.cpp b/Source/modules/mediasource/MediaSource.cpp
index 83f43652c05e79e59f5b8470d54a618ad4149f79..55c36d36dcb0943423012e91de1750b64cc33096 100644
--- a/Source/modules/mediasource/MediaSource.cpp
+++ b/Source/modules/mediasource/MediaSource.cpp
@@ -156,7 +156,6 @@ SourceBuffer* MediaSource::addSourceBuffer(const String& type, ExceptionState& e
     SourceBuffer* buffer = SourceBuffer::create(webSourceBuffer.release(), this, m_asyncEventQueue.get());
     // 6. Add the new object to sourceBuffers and fire a addsourcebuffer on that object.
     m_sourceBuffers->add(buffer);
-    m_activeSourceBuffers->add(buffer);
     // 7. Return the new object to the caller.
     return buffer;
 }
@@ -481,6 +480,28 @@ bool MediaSource::isOpen() const
     return readyState() == openKeyword();
 }
 
+void MediaSource::setSourceBufferActive(SourceBuffer* sourceBuffer)
+{
+    // https://dvcs.w3.org/hg/html-media/raw-file/tip/media-source/media-source.html#widl-MediaSource-activeSourceBuffers
+    // SourceBuffer objects in SourceBuffer.activeSourceBuffers must appear in
+    // the same order as they appear in SourceBuffer.sourceBuffers.
+    // SourceBuffer transitions to active are not guaranteed to occur in the
+    // same order as buffers in |m_sourceBuffers|, so this method needs to
+    // insert |sourceBuffer| into |m_activeSourceBuffers|.
+    size_t indexInSourceBuffers = m_sourceBuffers->find(sourceBuffer);
+    ASSERT(indexInSourceBuffers != kNotFound);
+
+    size_t insertPosition = 0;
+    while (insertPosition < m_activeSourceBuffers->length()) {
+        if (m_sourceBuffers->find(m_activeSourceBuffers->item(insertPosition)) >= indexInSourceBuffers)

[acolwell GONE FROM CHROMIUM, 2014/09/09 22:23:21]

nit: Reverse and merge into while condition?

[wolenetz, 2014/09/10 00:42:29]

Done.

+            break;
+
+        ++insertPosition;
+    }
+
+    m_activeSourceBuffers->insert(insertPosition, sourceBuffer);
+}
+
 bool MediaSource::isClosed() const
 {
     return readyState() == closedKeyword();