[Mojo Video Capture] Add support to BuildableVideoCaptureDevice for aborting the device start.

content/browser/renderer_host/media/buildable_video_capture_device.h

 // Copyright 2017 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.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_MEDIA_BUILDABLE_VIDEO_CAPTURE_DEVICE_H_
 #define CONTENT_BROWSER_RENDERER_HOST_MEDIA_BUILDABLE_VIDEO_CAPTURE_DEVICE_H_
 
 #include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted.h"
 #include "content/public/common/media_stream_request.h"
@@ skipping 18 matching lines @@
  public:
   class CONTENT_EXPORT Callbacks {
    public:
     virtual ~Callbacks() {}
     // Returns nullptr if no descriptor was found.
     virtual const media::VideoCaptureDeviceDescriptor* LookupDeviceDescriptor(
         const std::string& id) = 0;
     virtual void WillStartDevice(media::VideoFacingMode facing_mode) = 0;
     virtual void DidStartDevice(VideoCaptureController* controller) = 0;
     virtual void OnDeviceStartFailed(VideoCaptureController* controller) = 0;
+    virtual void OnDeviceStartAborted() = 0;
   };
 
   virtual ~BuildableVideoCaptureDevice() {}
 
   // Device management methods.
   virtual void CreateAndStartDeviceAsync(
       VideoCaptureController* controller,
       const media::VideoCaptureParams& params,
       Callbacks* callbacks,
       base::OnceClosure done_cb) = 0;
@@ skipping 15 matching lines @@
   virtual void RequestRefreshFrame() = 0;
 
   // Methods for specific types of devices.
   virtual void SetDesktopCaptureWindowIdAsync(gfx::NativeViewId window_id,
                                               base::OnceClosure done_cb) = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_BUILDABLE_VIDEO_CAPTURE_DEVICE_H_