Mac Video Capture: correct to float the erroneous handling of frame rate as int.

media/video/capture/mac/platform_video_capturing_mac.h

 // Copyright 2013 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 MEDIA_VIDEO_CAPTURE_MAC_PLATFORM_VIDEO_CAPTURING_MAC_H_
 #define MEDIA_VIDEO_CAPTURE_MAC_PLATFORM_VIDEO_CAPTURING_MAC_H_
 
 #import <Foundation/Foundation.h>
 
 namespace media {
@@ skipping 18 matching lines @@
 - (void)setFrameReceiver:(media::VideoCaptureDeviceMac*)frameReceiver;
 
 // Sets which capture device to use by name passed as deviceId argument. The
 // device names are usually obtained via VideoCaptureDevice::GetDeviceNames()
 // method. This method will also configure all device properties except those in
 // setCaptureHeight:widht:frameRate. If |deviceId| is nil, all potential
 // configuration is torn down. Returns YES on sucess, NO otherwise.
 - (BOOL)setCaptureDevice:(NSString*)deviceId;
 
 // Configures the capture properties.
-- (BOOL)setCaptureHeight:(int)height width:(int)width frameRate:(int)frameRate;
+- (BOOL)setCaptureHeight:(int)height
+                   width:(int)width
+               frameRate:(float)frameRate;
 
 // Start video capturing, register observers. Returns YES on sucess, NO
 // otherwise.
 - (BOOL)startCapture;
 
 // Stops video capturing, unregisters observers.
 - (void)stopCapture;
 
 @end
 
 #endif  // MEDIA_VIDEO_CAPTURE_MAC_PLATFORM_VIDEO_CAPTURING_MAC_H_