Obj-C SDK Cleanup

This CL separates the files under sdk/objc into logical directories, replacing
the previous file layout under Framework/.

A long term goal is to have some system set up to generate the files under
sdk/objc/api (the PeerConnection API wrappers) from the C++ code. In the shorter
term the goal is to abstract out shared concepts from these classes in order to
make them as uniform as possible.

The separation into base/, components/, and helpers/ are to differentiate between
the base layer's common protocols, various utilities and the actual platform
specific components.

The old directory layout that resembled a framework's internal layout is not
necessary, since it is generated by the framework target when building it.

Bug: webrtc:9627
Change-Id: Ib084fd83f050ae980649ca99e841f4fb0580bd8f
Reviewed-on: https://webrtc-review.googlesource.com/94142
Reviewed-by: Kári Helgason <kthelgason@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Rasmus Brandt <brandtr@webrtc.org>
Reviewed-by: Henrik Andreassson <henrika@webrtc.org>
Commit-Queue: Anders Carlsson <andersc@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24493}
diff --git a/sdk/objc/Framework/Headers/WebRTC/RTCRtpParameters.h b/sdk/objc/Framework/Headers/WebRTC/RTCRtpParameters.h
index 8f09934..0e5b7e2 100644
--- a/sdk/objc/Framework/Headers/WebRTC/RTCRtpParameters.h
+++ b/sdk/objc/Framework/Headers/WebRTC/RTCRtpParameters.h
@@ -8,36 +8,4 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#import <Foundation/Foundation.h>
-
-#import <WebRTC/RTCMacros.h>
-#import <WebRTC/RTCRtcpParameters.h>
-#import <WebRTC/RTCRtpCodecParameters.h>
-#import <WebRTC/RTCRtpEncodingParameters.h>
-#import <WebRTC/RTCRtpHeaderExtension.h>
-
-NS_ASSUME_NONNULL_BEGIN
-
-RTC_EXPORT
-@interface RTCRtpParameters : NSObject
-
-/** A unique identifier for the last set of parameters applied. */
-@property(nonatomic, copy) NSString *transactionId;
-
-/** Parameters used for RTCP. */
-@property(nonatomic, readonly, copy) RTCRtcpParameters *rtcp;
-
-/** An array containing parameters for RTP header extensions. */
-@property(nonatomic, readonly, copy) NSArray<RTCRtpHeaderExtension *> *headerExtensions;
-
-/** The currently active encodings in the order of preference. */
-@property(nonatomic, copy) NSArray<RTCRtpEncodingParameters *> *encodings;
-
-/** The negotiated set of send codecs in order of preference. */
-@property(nonatomic, copy) NSArray<RTCRtpCodecParameters *> *codecs;
-
-- (instancetype)init NS_DESIGNATED_INITIALIZER;
-
-@end
-
-NS_ASSUME_NONNULL_END
+#import "api/peerconnection/RTCRtpParameters.h"