scale with conversion using 2 steps with unittest

source/scale_argb.cc

Index: source/scale_argb.cc
diff --git a/source/scale_argb.cc b/source/scale_argb.cc
index 40a2d1ab205eb0c5672b8883a2fb0e3122b667d7..132581cce855dd52f7b1ee784fb381b3ebb2ac86 100644
--- a/source/scale_argb.cc
+++ b/source/scale_argb.cc
@@ -847,6 +847,37 @@ int ARGBScale(const uint8* src_argb, int src_stride_argb,
   return 0;
 }
 
+// Scale with YUV conversion to ARGB and clipping.
+LIBYUV_API
+int YUVToARGBScaleClip(const uint8* src_y, int src_stride_y,
+                       const uint8* src_u, int src_stride_u,
+                       const uint8* src_v, int src_stride_v,
+                       uint32 src_fourcc,
+                       int src_width, int src_height,
+                       uint8* dst_argb, int dst_stride_argb,
+                       uint32 dst_fourcc,
+                       int dst_width, int dst_height,
+                       int clip_x, int clip_y, int clip_width, int clip_height,
+                       enum FilterMode filtering) {
+
+  uint8* argb_buffer = (uint8*)malloc(src_width * src_height * 4);
+  int r;
+  I420ToARGB(src_y, src_stride_y,
+             src_u, src_stride_u,
+             src_v, src_stride_v,
+             argb_buffer, src_width * 4,
+             src_width, src_height);
+
+  r = ARGBScaleClip(argb_buffer, src_width * 4,
+                    src_width, src_height,
+                    dst_argb, dst_stride_argb,
+                    dst_width, dst_height,
+                    clip_x, clip_y, clip_width, clip_height,
+                    filtering);
+  free(argb_buffer);
+  return r;
+}
+
 #ifdef __cplusplus
 }  // extern "C"
 }  // namespace libyuv