Correct browser side audio effect state for mediastream requests.

content/browser/renderer_host/media/media_stream_manager.cc

Index: content/browser/renderer_host/media/media_stream_manager.cc
diff --git a/content/browser/renderer_host/media/media_stream_manager.cc b/content/browser/renderer_host/media/media_stream_manager.cc
index 21d2aa4ce2e1ce7c0da8cbdc3fbe1b9887938152..cdb71b1a6a56aad9cece3a7fd7ed80d97a25672a 100644
--- a/content/browser/renderer_host/media/media_stream_manager.cc
+++ b/content/browser/renderer_host/media/media_stream_manager.cc
@@ -118,6 +118,18 @@ void ParseStreamType(const StreamOptions& options,
   }
 }
 
+// Turns off available audio effects (removes the flag) if the options
+// explicitly turn them off.
+void FilterAudioEffects(const StreamOptions& options, int* effects) {
+  DCHECK(effects);
+  // TODO(ajm): Should we also handle ECHO_CANCELLER here?
+  std::string value;
+  if (options.GetFirstAudioConstraintByName(
+          kMediaStreamAudioDucking, &value, NULL) && value == "false") {
+    *effects &= ~media::AudioParameters::DUCKING;
+  }
+}
+
 // Private helper method for SendMessageToNativeLog() that obtains the global
 // MediaStreamManager instance on the UI thread before sending |message| to the
 // webrtcLoggingPrivate API.
@@ -1386,8 +1398,12 @@ bool MediaStreamManager::FindExistingRequestedDeviceInfo(
            device_it != request->devices.end(); ++device_it) {
         if (device_it->device.id == source_id &&
             device_it->device.type == new_device_info.type) {
-            *existing_device_info = *device_it;
-            *existing_request_state = request->state(device_it->device.type);
+          *existing_device_info = *device_it;
+          // Make sure that the audio |effects| reflect what the request
+          // is set to and not what the capabilities are.
+          FilterAudioEffects(request->options,
+              &existing_device_info->device.input.effects);
+          *existing_request_state = request->state(device_it->device.type);
           return true;
         }
       }
@@ -1568,6 +1584,14 @@ void MediaStreamManager::Opened(MediaStreamType stream_type,
                 audio_input_device_manager_->GetOpenedDeviceInfoById(
                     device_it->session_id);
             device_it->device.input = info->device.input;
+
+            // Since the audio input device manager will set the input
+            // parameters to the default settings (including supported effects),
+            // we need to adjust those settings here according to what the
+            // request asks for.
+            FilterAudioEffects(request->options,
+                &device_it->device.input.effects);
+
             device_it->device.matched_output = info->device.matched_output;
           }
         }