Fix for RtcEventLog ObjC interface

This moves the RtcEventLog start/stop functions to PeerConnection on the objC interface.

BUG=
R=tkchin@webrtc.org

Review URL: https://codereview.webrtc.org/2106103003 .

Cr-Commit-Position: refs/heads/master@{#13337}

webrtc/sdk/objc/Framework/Headers/WebRTC/RTCPeerConnection.h

@@ -183,6 +183,11 @@ RTC_EXPORT
            completionHandler:
     (nullable void (^)(NSError * _Nullable error))completionHandler;
 
+/** Start or stop recording an Rtc EventLog. */
+- (BOOL)startRtcEventLogWithFilePath:(NSString *)filePath
+                      maxSizeInBytes:(int64_t)maxSizeInBytes;
+- (void)stopRtcEventLog;
+
 @end
 
 @interface RTCPeerConnection (Media)

webrtc/sdk/objc/Framework/Headers/WebRTC/RTCPeerConnectionFactory.h

@@ -53,11 +53,6 @@ RTC_EXPORT
                                               delegate:
     (nullable id<RTCPeerConnectionDelegate>)delegate;
 
-/** Temporary interface. Use at your own risk. See peerconnectioninterface.h for details. */
-- (BOOL)startRtcEventLogWithFilePath:(NSString *)filePath
-                      maxSizeInBytes:(int64_t)maxSizeInBytes;
-- (void)stopRtcEventLog;
-
 @end
 
 NS_ASSUME_NONNULL_END