Removed file RTCCameraVideoCapturer.mm that isn't needed

webrtc/sdk/objc/Framework/Classes/Video/AVCaptureSession+Device.mm

-/*
- *  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.
- */
-
-#import "AVCaptureSession+Device.h"
-
-BOOL CFStringContainsString(CFStringRef theString, CFStringRef stringToFind) {
-  return CFStringFindWithOptions(theString,
-                                 stringToFind,
-                                 CFRangeMake(0, CFStringGetLength(theString)),
-                                 kCFCompareCaseInsensitive,
-                                 nil);
-}
-
-@implementation AVCaptureSession (Device)
-
-+ (AVCaptureDevicePosition)devicePositionForSampleBuffer:(CMSampleBufferRef)sampleBuffer {
-  // Check the image's EXIF for the camera the image came from.
-  AVCaptureDevicePosition cameraPosition = AVCaptureDevicePositionUnspecified;
-  CFDictionaryRef attachments = CMCopyDictionaryOfAttachments(
-      kCFAllocatorDefault, sampleBuffer, kCMAttachmentMode_ShouldPropagate);
-  if (attachments) {
-    int size = CFDictionaryGetCount(attachments);
-    if (size > 0) {
-      CFDictionaryRef cfExifDictVal = nil;
-      if (CFDictionaryGetValueIfPresent(
-              attachments, (const void *)CFSTR("{Exif}"), (const void **)&cfExifDictVal)) {
-        CFStringRef cfLensModelStrVal;
-        if (CFDictionaryGetValueIfPresent(cfExifDictVal,
-                                          (const void *)CFSTR("LensModel"),
-                                          (const void **)&cfLensModelStrVal)) {
-          if (CFStringContainsString(cfLensModelStrVal, CFSTR("front"))) {
-            cameraPosition = AVCaptureDevicePositionFront;
-          } else if (CFStringContainsString(cfLensModelStrVal, CFSTR("back"))) {
-            cameraPosition = AVCaptureDevicePositionBack;
-          }
-        }
-      }
-    }
-    CFRelease(attachments);
-  }
-  return cameraPosition;
-}
-
-@end