Always apply UniformMatrix4fvStreamTextureMatrixCHROMIUM matrix argument.

cc/output/shader.cc

Index: cc/output/shader.cc
diff --git a/cc/output/shader.cc b/cc/output/shader.cc
index 75cac6cbfd61f1c35250ab96e70b822eb621a04a..e20ea4292e15326137cad7d60603e716486472f6 100644
--- a/cc/output/shader.cc
+++ b/cc/output/shader.cc
@@ -751,8 +751,7 @@ std::string VertexShaderVideoTransform::GetShaderBody() {
   return SHADER0([]() {
     void main() {
       gl_Position = matrix * a_position;
-      v_texCoord =
-          vec2(texMatrix * vec4(a_texCoord.x, 1.0 - a_texCoord.y, 0.0, 1.0));
+      v_texCoord = (texMatrix * vec4(a_texCoord.xy, 0.0, 1.0)).xy;
     }
   });
 }