Remove dependencies on modules:module_api from AudioProcessing.

- Directly include api/audio/audio_frame.h everywhere AudioFrame is used.
- This *will* remove transient dependencies on libjpeg and a bunch of other things from the e.g. APM.
- audio_frame.h still included from module_common_types.h for backwards compatibility with clients.

Bug: webrtc:9139, webrtc:7504
Change-Id: Id96f9268c01667fbcc29a01f5c1dd25a37836897
Reviewed-on: https://webrtc-review.googlesource.com/62464
Commit-Queue: Fredrik Solenberg <solenberg@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22845}
diff --git a/api/audio/audio_frame.h b/api/audio/audio_frame.h
index d69f607..39840e5 100644
--- a/api/audio/audio_frame.h
+++ b/api/audio/audio_frame.h
@@ -11,6 +11,8 @@
 #ifndef API_AUDIO_AUDIO_FRAME_H_
 #define API_AUDIO_AUDIO_FRAME_H_
 
+#include <stddef.h>
+
 #include "rtc_base/constructormagic.h"
 #include "typedefs.h"  // NOLINT(build/include)