Delete AndroidVideoCapturer::FrameFactory.

Splits VideoCapturer::OnFrameCaptured into helper methods,
which enables use of the VideoAdaptation logic without
using a frame factory.

Refactors AndroidVideoCapturer to make adaptation decision
earlier, so we can crop and rotate using
NV12ToI420Rotate.

BUG=webrtc:5682

Review-Url: https://codereview.webrtc.org/1973873003
Cr-Commit-Position: refs/heads/master@{#12895}

webrtc/api/java/jni/native_handle_impl.h

@@ -18,14 +18,37 @@
 
 namespace webrtc_jni {
 
+// Open gl texture matrix, in column-major order. Operations are
+// in-place.
+class Matrix {
+ public:
+  Matrix(JNIEnv* jni, jfloatArray a);
+
+  jfloatArray ToJava(JNIEnv* jni);
+
+  // Crop arguments are relative to original size.
+  void Crop(float cropped_width,
+            float cropped_height,
+            float crop_x,
+            float crop_y);
+
+  void Rotate(webrtc::VideoRotation rotation);
+
+ private:
+  static void Multiply(const float a[16], const float b[16], float result[16]);
+  float elem_[16];
+};
+
 // Wrapper for texture object.
 struct NativeHandleImpl {
   NativeHandleImpl(JNIEnv* jni,
                    jint j_oes_texture_id,
                    jfloatArray j_transform_matrix);
 
+  NativeHandleImpl(int id, const Matrix& matrix);
+
   const int oes_texture_id;
-  float sampling_matrix[16];
+  Matrix sampling_matrix;
 };
 
 class AndroidTextureBuffer : public webrtc::NativeHandleBuffer {
@@ -42,6 +65,8 @@ class AndroidTextureBuffer : public webrtc::NativeHandleBuffer {
   rtc::scoped_refptr<AndroidTextureBuffer> CropScaleAndRotate(
       int cropped_width,
       int cropped_height,
+      int crop_x,
+      int crop_y,
       int dst_width,
       int dst_height,
       webrtc::VideoRotation rotation);