Fix video slow to appear on first launch.

webrtc/sdk/objc/Framework/Classes/PeerConnection/RTCCameraVideoCapturer.m

 /*
  *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 123 matching lines @@
                       _currentDevice = device;
 
                       NSError *error = nil;
                       if (![_currentDevice lockForConfiguration:&error]) {
                         RTCLogError(
                             @"Failed to lock device %@. Error: %@", _currentDevice, error.userInfo);
                         return;
                       }
                       [self reconfigureCaptureSessionInput];
                       [self updateOrientation];
+                      [self updateDeviceCaptureFormat:format fps:fps];
                       [_captureSession startRunning];
-                      [self updateDeviceCaptureFormat:format fps:fps];
                       [_currentDevice unlockForConfiguration];
                       _isRunning = YES;
                     }];
 }
 
 - (void)stopCapture {
   _willBeRunning = NO;
   [RTCDispatcher
       dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
                     block:^{
@@ skipping 282 matching lines @@
 
 - (void)updateOrientation {
   NSAssert([RTCDispatcher isOnQueueForType:RTCDispatcherTypeCaptureSession],
            @"updateOrientation must be called on the capture queue.");
 #if TARGET_OS_IPHONE
   _orientation = [UIDevice currentDevice].orientation;
 #endif
 }
 
 @end