Move Objective-C video renderers to webrtc/api/objc.

webrtc/api/objc/RTCEAGLVideoView.h

Index: webrtc/api/objc/RTCEAGLVideoView.h
diff --git a/webrtc/base/objc/NSString+StdString.h b/webrtc/api/objc/RTCEAGLVideoView.h
similarity index 53%
copy from webrtc/base/objc/NSString+StdString.h
copy to webrtc/api/objc/RTCEAGLVideoView.h
index 8bf6cc94be0346e398ab1a980af6378f06ccb7a5..1a57df76bbe93ede2764cb55cbf912da25c8016d 100644
--- a/webrtc/base/objc/NSString+StdString.h
+++ b/webrtc/api/objc/RTCEAGLVideoView.h
@@ -9,17 +9,26 @@
  */
 
 #import <Foundation/Foundation.h>
+#import <UIKit/UIKit.h>
 
-#include <string>
+#import "RTCVideoRenderer.h"
 
 NS_ASSUME_NONNULL_BEGIN
 
-@interface NSString (StdString)
+@class RTCEAGLVideoView;
+@protocol RTCEAGLVideoViewDelegate
 
-@property(nonatomic, readonly) std::string stdString;
+- (void)videoView:(RTCEAGLVideoView *)videoView didChangeVideoSize:(CGSize)size;
 
-+ (std::string)stdStringForString:(NSString *)nsString;
-+ (NSString *)stringForStdString:(const std::string&)stdString;
+@end
+
+/**
+ * RTCEAGLVideoView is an RTCVideoRenderer which renders video frames in its
+ * bounds using OpenGLES 2.0.
+ */
+@interface RTCEAGLVideoView : UIView <RTCVideoRenderer>
+
+@property(nonatomic, weak) id<RTCEAGLVideoViewDelegate> delegate;
 
 @end