Create a private API for controlling WebRTC's AEC3

content/browser/renderer_host/render_process_host_impl.h

Index: content/browser/renderer_host/render_process_host_impl.h
diff --git a/content/browser/renderer_host/render_process_host_impl.h b/content/browser/renderer_host/render_process_host_impl.h
index 4405d667996f47a12fcb91145c8edf5d2647c2b9..c9c8d865685847998ef36ecc8eddae8adca20e6d 100644
--- a/content/browser/renderer_host/render_process_host_impl.h
+++ b/content/browser/renderer_host/render_process_host_impl.h
@@ -156,6 +156,7 @@ class CONTENT_EXPORT RenderProcessHostImpl
   void DisableAudioDebugRecordings() override;
   bool StartWebRTCEventLog(const base::FilePath& file_path) override;
   bool StopWebRTCEventLog() override;
+  void SetEchoCanceller3(bool enable) override;
   void SetWebRtcLogMessageCallback(
       base::Callback<void(const std::string&)> callback) override;
   void ClearWebRtcLogMessageCallback() override;
@@ -395,6 +396,7 @@ class CONTENT_EXPORT RenderProcessHostImpl
                                  IPC::PlatformFileForTransit file_for_transit);
   void SendDisableAecDumpToRenderer();
   base::FilePath GetAecDumpFilePathWithExtensions(const base::FilePath& file);
+  void SetEchoCanceller3ForId(bool enable, int id);
 #endif
 
   static void OnMojoError(int render_process_id, const std::string& error);