Android: Annotate and generate JNI code for VideoFrame.java

This CL also merged native_handle_impl.cc and videoframe_jni.cc to keep
all JNI code for the same Java class in the same file, and also renames
this file to jni/videoframe.cc.

The classes AndroidVideoBufferFactory and JavaVideoFrameFactory are
now unnecessary since we cache everything and can be simplified to
global static functions instead.

Bug: webrtc:8278
Change-Id: I03d7b0bbde64cfb407cd6210478ddf9d5599cd8c
Reviewed-on: https://webrtc-review.googlesource.com/22923
Commit-Queue: Magnus Jedvert <magjed@webrtc.org>
Reviewed-by: Sami Kalliomäki <sakal@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20677}
diff --git a/sdk/android/src/jni/androidmediadecoder_jni.cc b/sdk/android/src/jni/androidmediadecoder_jni.cc
index 344a4ca..613bb54 100644
--- a/sdk/android/src/jni/androidmediadecoder_jni.cc
+++ b/sdk/android/src/jni/androidmediadecoder_jni.cc
@@ -17,9 +17,6 @@
 // androidmediacodeccommon.h to avoid build errors.
 #include "sdk/android/src/jni/androidmediadecoder_jni.h"
 
-#include "third_party/libyuv/include/libyuv/convert.h"
-#include "third_party/libyuv/include/libyuv/convert_from.h"
-#include "third_party/libyuv/include/libyuv/video_common.h"
 #include "common_video/h264/h264_bitstream_parser.h"
 #include "common_video/include/i420_buffer_pool.h"
 #include "modules/video_coding/include/video_codec_interface.h"
@@ -32,8 +29,11 @@
 #include "rtc_base/timeutils.h"
 #include "sdk/android/src/jni/androidmediacodeccommon.h"
 #include "sdk/android/src/jni/classreferenceholder.h"
-#include "sdk/android/src/jni/native_handle_impl.h"
 #include "sdk/android/src/jni/surfacetexturehelper_jni.h"
+#include "sdk/android/src/jni/videoframe.h"
+#include "third_party/libyuv/include/libyuv/convert.h"
+#include "third_party/libyuv/include/libyuv/convert_from.h"
+#include "third_party/libyuv/include/libyuv/video_common.h"
 
 using rtc::Bind;
 using rtc::Thread;