Implement device enumeration for PPB_VideoCapture_Dev.

ppapi/thunk/ppb_video_capture_api.h

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
 #ifndef PPAPI_THUNK_VIDEO_CAPTURE_API_H_
 #define PPAPI_THUNK_VIDEO_CAPTURE_API_H_
 
+#include <string>
+#include <vector>
+
 #include "ppapi/c/dev/ppb_video_capture_dev.h"
 
 namespace ppapi {
+
+struct DeviceRefData;
+
 namespace thunk {
 
 class PPB_VideoCapture_API {
  public:
   virtual ~PPB_VideoCapture_API() {}
 
+  virtual int32_t EnumerateDevices(PP_CompletionCallback callback) = 0;
+  virtual PP_Resource GetDevices() = 0;
   virtual int32_t StartCapture(
+      const std::string& device_id,
       const PP_VideoCaptureDeviceInfo_Dev& requested_info,
       uint32_t buffer_count) = 0;
   virtual int32_t ReuseBuffer(uint32_t buffer) = 0;
   virtual int32_t StopCapture() = 0;
+
+  // This function is not exposed through the C API, but returns the internal
+  // data for easy proxying.
+  virtual const std::vector<DeviceRefData>& GetDeviceRefData() const = 0;
 };
 
 }  // namespace thunk
 }  // namespace ppapi
 
 #endif  // PPAPI_THUNK_VIDEO_CAPTURE_API_H_