Clamp YUV videos to their visible size in the shader

cc/output/shader.h

Index: cc/output/shader.h
diff --git a/cc/output/shader.h b/cc/output/shader.h
index 8c1f2647946906b1a87ce00618b3ba3384c020ca..2ecc0a4ed4d5fe0a4be3ee905d79bbb5ea4b9aeb 100644
--- a/cc/output/shader.h
+++ b/cc/output/shader.h
@@ -104,11 +104,13 @@ class VertexShaderPosTexYUVStretchOffset {
   int matrix_location() const { return matrix_location_; }
   int tex_scale_location() const { return tex_scale_location_; }
   int tex_offset_location() const { return tex_offset_location_; }
+  int clamp_size_location() const { return clamp_size_location_; }
 
  private:
   int matrix_location_;
   int tex_scale_location_;
   int tex_offset_location_;
+  int clamp_size_location_;
 
   DISALLOW_COPY_AND_ASSIGN(VertexShaderPosTexYUVStretchOffset);
 };