Mac: Add flag to force QTKit in otherwise AVFoundation-enabled builds/configs

media/base/media_switches.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/base/media_switches.h"
 
 namespace switches {
 
 // Allow users to specify a custom buffer size for debugging purpose.
 const char kAudioBufferSize[] = "audio-buffer-size";
@@ skipping 22 matching lines @@
 #endif
 
 #if defined(OS_MACOSX)
 // AVFoundation is available in versions 10.7 and onwards, and is to be used
 // http://crbug.com/288562 for both audio and video device monitoring and for
 // video capture. Being a dynamically loaded NSBundle and library, it hits the
 // Chrome startup time (http://crbug.com/311325 and http://crbug.com/311437);
 // for experimentation purposes, in particular library load time issue, the
 // usage of this library can be enabled by using this flag.
 const char kEnableAVFoundation[] = "enable-avfoundation";
+// QTKit is the media capture API predecessor to AVFoundation, available up and
+// until Mac OS X 10.9 (despite being deprecated in this last one). This flag
+// is used for troubleshooting and testing, and forces QTKit in builds and
+// configurations where AVFoundation would be used otherwise.
+const char kForceQTKit[] = "force-qtkit";
 #endif
 
 #if defined(OS_WIN)
 // Use exclusive mode audio streaming for Windows Vista and higher.
 // Leads to lower latencies for audio streams which uses the
 // AudioParameters::AUDIO_PCM_LOW_LATENCY audio path.
 // See http://msdn.microsoft.com/en-us/library/windows/desktop/dd370844.aspx
 // for details.
 const char kEnableExclusiveAudio[] = "enable-exclusive-audio";
 
@@ skipping 24 matching lines @@
 
 #if defined(USE_CRAS)
 // Use CRAS, the ChromeOS audio server.
 const char kUseCras[] = "use-cras";
 #endif
 
 // Use a raw video file as fake video capture device.
 const char kUseFileForFakeVideoCapture[] = "use-file-for-fake-video-capture";
 
 }  // namespace switches