Add WebKit prefix to MediaSource,SourceBuffer, and SourceBufferList objects.

Source/modules/modules.gypi

Index: Source/modules/modules.gypi
diff --git a/Source/modules/modules.gypi b/Source/modules/modules.gypi
index 5ce9d3460f0d4e1ebced2c26487eecccc1ea8a80..e624eaacaef14edbc8d76d45f595d19dab8f7477 100644
--- a/Source/modules/modules.gypi
+++ b/Source/modules/modules.gypi
@@ -57,9 +57,9 @@
       'indexeddb/IDBTransaction.idl',
       'indexeddb/IDBVersionChangeEvent.idl',
       'indexeddb/WorkerContextIndexedDatabase.idl',
-      'mediasource/MediaSource.idl',
-      'mediasource/SourceBuffer.idl',
-      'mediasource/SourceBufferList.idl',
+      'mediasource/WebKitMediaSource.idl',
+      'mediasource/WebKitSourceBuffer.idl',
+      'mediasource/WebKitSourceBufferList.idl',
       'mediastream/MediaStream.idl',
       'mediastream/MediaStreamEvent.idl',
       'mediastream/MediaStreamTrack.idl',
@@ -328,14 +328,14 @@
       'indexeddb/WorkerContextIndexedDatabase.h',
       'indexeddb/chromium/IDBFactoryBackendInterfaceChromium.cpp',
       'indexeddb/chromium/IDBFactoryBackendInterfaceChromium.h',
-      'mediasource/MediaSource.cpp',
-      'mediasource/MediaSource.h',
       'mediasource/MediaSourceRegistry.cpp',
       'mediasource/MediaSourceRegistry.h',
-      'mediasource/SourceBuffer.cpp',
-      'mediasource/SourceBuffer.h',
-      'mediasource/SourceBufferList.cpp',
-      'mediasource/SourceBufferList.h',
+      'mediasource/WebKitMediaSource.cpp',
+      'mediasource/WebKitMediaSource.h',
+      'mediasource/WebKitSourceBuffer.cpp',
+      'mediasource/WebKitSourceBuffer.h',
+      'mediasource/WebKitSourceBufferList.cpp',
+      'mediasource/WebKitSourceBufferList.h',
       'mediastream/MediaConstraintsImpl.cpp',
       'mediastream/MediaConstraintsImpl.h',
       'mediastream/MediaStream.cpp',