Android: Generate Java -> C++ JNI code for VideoEncoder

This is the first CL that tries generating Java -> C++ JNI code.

Bug: webrtc:8278
Change-Id: I1ff0df10db0f80a3c84a61a4e82be8f713690a69
Reviewed-on: https://webrtc-review.googlesource.com/20873
Commit-Queue: Magnus Jedvert <magjed@webrtc.org>
Reviewed-by: Sami Kalliomäki <sakal@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20592}

sdk/android/src/jni/jni_generator_helper.h

@@ -19,9 +19,12 @@
 #include "sdk/android/src/jni/jni_helpers.h"
 
 #define CHECK_CLAZZ(env, jcaller, clazz, ...) RTC_DCHECK(clazz);
+#define CHECK_NATIVE_PTR(env, jcaller, native_ptr, method_name, ...) \
+  RTC_DCHECK(native_ptr) << method_name;
 
 #define BASE_EXPORT
 #define JNI_REGISTRATION_EXPORT __attribute__((visibility("default")))
+#define JNI_GENERATOR_EXPORT extern "C" JNIEXPORT JNICALL
 
 namespace jni_generator {
 inline void CheckException(JNIEnv* env) {
@@ -70,6 +73,8 @@ class JavaRef {
 // using DeleteLocalRef though.
 template <typename T>
 using ScopedJavaLocalRef = JavaRef<T>;
+template <typename T>
+using JavaParamRef = JavaRef<T>;
 
 // This function will initialize |atomic_class_id| to contain a global ref to
 // the given class, and will return that ref on subsequent calls. The caller is

sdk/android/src/jni/videoencoderwrapper.cc

@@ -192,6 +192,7 @@ const char* VideoEncoderWrapper::ImplementationName() const {
 }
 
 void VideoEncoderWrapper::OnEncodedFrame(JNIEnv* jni,
+                                         jobject j_caller,
                                          jobject j_buffer,
                                          jint encoded_width,
                                          jint encoded_height,
@@ -402,25 +403,5 @@ std::string VideoEncoderWrapper::GetImplementationName(JNIEnv* jni) const {
   return JavaToStdString(jni, jname);
 }
 
-JNI_FUNCTION_DECLARATION(void,
-                         VideoEncoderWrapper_onEncodedFrame,
-                         JNIEnv* jni,
-                         jclass,
-                         jlong j_native_encoder,
-                         jobject buffer,
-                         jint encoded_width,
-                         jint encoded_height,
-                         jlong capture_time_ns,
-                         jint frame_type,
-                         jint rotation,
-                         jboolean complete_frame,
-                         jobject qp) {
-  VideoEncoderWrapper* native_encoder =
-      reinterpret_cast<VideoEncoderWrapper*>(j_native_encoder);
-  native_encoder->OnEncodedFrame(jni, buffer, encoded_width, encoded_height,
-                                 capture_time_ns, frame_type, rotation,
-                                 complete_frame, qp);
-}
-
 }  // namespace jni
 }  // namespace webrtc

sdk/android/src/jni/videoencoderwrapper.h

@@ -55,6 +55,7 @@ class VideoEncoderWrapper : public VideoEncoder {
 
   // Should only be called by JNI.
   void OnEncodedFrame(JNIEnv* jni,
+                      jobject j_caller,
                       jobject j_buffer,
                       jint encoded_width,
                       jint encoded_height,