Android: Add common function for adding/releasing native reference

webrtc/sdk/android/src/jni/wrapped_native_i420_buffer.cc

Index: webrtc/sdk/android/src/jni/wrapped_native_i420_buffer.cc
diff --git a/webrtc/sdk/android/src/jni/wrapped_native_i420_buffer.cc b/webrtc/sdk/android/src/jni/wrapped_native_i420_buffer.cc
index ea83597aeae5a71b74b427b5c55c85df0f50d72f..6a819e4a26fb0741b14453721723f8008d43cdde 100644
--- a/webrtc/sdk/android/src/jni/wrapped_native_i420_buffer.cc
+++ b/webrtc/sdk/android/src/jni/wrapped_native_i420_buffer.cc
@@ -46,20 +46,4 @@ jobject WrapI420Buffer(
   return j_wrapped_native_i420_buffer;
 }
 
-JNI_FUNCTION_DECLARATION(void,
-                         WrappedNativeI420Buffer_nativeAddRef,
-                         JNIEnv* jni,
-                         jclass,
-                         jlong j_buffer_pointer) {
-  reinterpret_cast<webrtc::VideoFrameBuffer*>(j_buffer_pointer)->AddRef();
-}
-
-JNI_FUNCTION_DECLARATION(void,
-                         WrappedNativeI420Buffer_nativeRelease,
-                         JNIEnv* jni,
-                         jclass,
-                         jlong j_buffer_pointer) {
-  reinterpret_cast<webrtc::VideoFrameBuffer*>(j_buffer_pointer)->Release();
-}
-
 }  // namespace webrtc_jni