Enable platform echo cancellation through the AudioRecord path.

content/public/common/media_stream_request.h

Index: content/public/common/media_stream_request.h
diff --git a/content/public/common/media_stream_request.h b/content/public/common/media_stream_request.h
index e6870e150b09d024996e7f5eaa6806bea062b22b..30c5577e7ab548f03f693886219e71126c854edb 100644
--- a/content/public/common/media_stream_request.h
+++ b/content/public/common/media_stream_request.h
@@ -13,6 +13,7 @@
 #include "base/callback_forward.h"
 #include "base/memory/scoped_ptr.h"
 #include "content/common/content_export.h"
+#include "media/audio/audio_parameters.h"

[ajm, 2013/12/10 06:37:16]

This trips a presubmit check:
"You added one or more #includes that violate checkdeps rules."

I suppose I'll have to copy over the definition of PlatformEffects? I'll do that
tomorrow.

[tommi (sloooow) - chröme, 2013/12/11 12:14:36]

Yes unfortunately.  That's why we're not using AudioParameters for sample rate,
channel layout etc here.  It would be good if we didn't have to have this here
though since I'm not convinced these details need to be a part of the public
content interface... hmm... no action on that in this cl though.

 #include "url/gurl.h"
 
 namespace content {
@@ -110,7 +111,7 @@ struct CONTENT_EXPORT MediaStreamDevice {
     }
 
     AudioDeviceParameters(int sample_rate, int channel_layout,
-                          int frames_per_buffer)
+        int frames_per_buffer)
         : sample_rate(sample_rate),
           channel_layout(channel_layout),
           frames_per_buffer(frames_per_buffer) {
@@ -129,6 +130,9 @@ struct CONTENT_EXPORT MediaStreamDevice {
     // expected browser side settings and avoid unnecessary buffering.
     // See media::AudioParameters for more.
     int frames_per_buffer;
+
+    // See media::AudioParameters.
+    media::AudioParameters::PlatformEffects effects;
   };
 
   // These below two member variables are valid only when the type of device is