Linux video capture: handle devices that don't enumerate any frame rates

media/video/capture/linux/video_capture_device_linux.h

 // 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.
 
 // Linux specific implementation of VideoCaptureDevice.
 // V4L2 is used for capturing. V4L2 does not provide its own thread for
 // capturing so this implementation uses a Chromium thread for fetching frames
 // from V4L2.
 
 #ifndef MEDIA_VIDEO_CAPTURE_LINUX_VIDEO_CAPTURE_DEVICE_LINUX_H_
@@ skipping 41 matching lines @@
   // Buffers used to receive video frames from with v4l2.
   struct Buffer {
     Buffer() : start(0), length(0) {}
     void* start;
     size_t length;
   };
 
   // Called on the v4l2_thread_.
   void OnAllocateAndStart(int width,
                           int height,
-                          int frame_rate,
+                          float frame_rate,
                           scoped_ptr<Client> client);
   void OnStopAndDeAllocate();
   void OnCaptureTask();
 
   bool AllocateVideoBuffers();
   void DeAllocateVideoBuffers();
   void SetErrorState(const std::string& reason);
 
   InternalState state_;
   scoped_ptr<VideoCaptureDevice::Client> client_;
   Name device_name_;
   base::ScopedFD device_fd_;  // File descriptor for the opened camera device.
   base::Thread v4l2_thread_;  // Thread used for reading data from the device.
   Buffer* buffer_pool_;
   int buffer_pool_size_;  // Number of allocated buffers.
   int timeout_count_;
   VideoCaptureFormat capture_format_;
 
   // Clockwise rotation in degrees.  This value should be 0, 90, 180, or 270.
   // This is only used on |v4l2_thread_| when it is running, or the constructor
   // thread otherwise.
   int rotation_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(VideoCaptureDeviceLinux);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_VIDEO_CAPTURE_LINUX_VIDEO_CAPTURE_DEVICE_LINUX_H_