compositor-worker: Introduce WebCompositorMutableState

ui/gfx/transform.h

Index: ui/gfx/transform.h
diff --git a/ui/gfx/transform.h b/ui/gfx/transform.h
index 26f7b9d2804c35e944750b7b83b498d37b1ee596..75c4797744a4310c569751bfc4380224286d5b84 100644
--- a/ui/gfx/transform.h
+++ b/ui/gfx/transform.h
@@ -40,6 +40,7 @@ class GFX_EXPORT Transform {
   // Initialize with the concatenation of lhs * rhs.
   Transform(const Transform& lhs, const Transform& rhs)
       : matrix_(lhs.matrix_, rhs.matrix_) {}
+  explicit Transform(const SkMatrix44& matrix) : matrix_(matrix) {}
   // Constructs a transform from explicit 16 matrix elements. Elements
   // should be given in row-major order.
   Transform(SkMScalar col1row1,