Output silence if the MediaElementAudioSourceNode has a different origin

Source/modules/webaudio/MediaElementAudioSourceNode.cpp

Index: Source/modules/webaudio/MediaElementAudioSourceNode.cpp
diff --git a/Source/modules/webaudio/MediaElementAudioSourceNode.cpp b/Source/modules/webaudio/MediaElementAudioSourceNode.cpp
index 12678d1a8f104f579e058d107a0045e73d529789..2abb368a76bad3c5fdf889c8231d69e397faa5c0 100644
--- a/Source/modules/webaudio/MediaElementAudioSourceNode.cpp
+++ b/Source/modules/webaudio/MediaElementAudioSourceNode.cpp
@@ -33,6 +33,8 @@
 #include "modules/webaudio/AudioNodeOutput.h"
 #include "platform/Logging.h"
 #include "platform/audio/AudioUtilities.h"
+#include "platform/graphics/media/MediaPlayer.h"
+#include "platform/weborigin/SecurityOrigin.h"
 #include "wtf/Locker.h"
 
 namespace blink {
@@ -117,6 +119,8 @@ void MediaElementAudioSourceNode::process(size_t numberOfFrames)
     MutexTryLocker tryLocker(m_processLock);
     if (tryLocker.locked()) {
         if (AudioSourceProvider* provider = mediaElement()->audioSourceProvider()) {
+            // Grab data from the provider so that the element continues to make progress, even if
+            // we're going to output silence anyway.
             if (m_multiChannelResampler.get()) {
                 ASSERT(m_sourceSampleRate != sampleRate());
                 m_multiChannelResampler->process(provider, outputBus, numberOfFrames);
@@ -125,6 +129,11 @@ void MediaElementAudioSourceNode::process(size_t numberOfFrames)
                 ASSERT(m_sourceSampleRate == sampleRate());
                 provider->provideInput(outputBus, numberOfFrames);
             }
+            // Output silence if we don't have access to the element.
+            if (!(mediaElement()->webMediaPlayer()->didPassCORSAccessCheck()
+                || context()->securityOrigin()->canRequest(mediaElement()->currentSrc()))) {

[Ken Russell (switch to Gerrit), 2015/02/04 01:28:19]

The indentation looks confusing here. I'd indent the || a couple more spaces to
be on the right hand side of the inner open-paren.
http://www.chromium.org/blink/coding-style#TOC-Line-breaking (not really covered
there)

[Raymond Toy, 2015/02/04 19:00:38]

Clang-format puts || under the "d" in mediaElement, which is nicer.

+                outputBus->zero();
+            }
         } else {
             // Either this port doesn't yet support HTMLMediaElement audio stream access,
             // or the stream is not yet available.