ui: Eliminate allocating gfx::Canvas on the heap for every view.

ui/gfx/canvas.cc

Index: ui/gfx/canvas.cc
diff --git a/ui/gfx/canvas.cc b/ui/gfx/canvas.cc
index 49822b71f11f758848865edce1dc079c642eb769..0c4a5a09363e66eed784d894a8bf870a9c91ceb6 100644
--- a/ui/gfx/canvas.cc
+++ b/ui/gfx/canvas.cc
@@ -59,13 +59,12 @@ Canvas::Canvas()
       canvas_(owned_canvas_.get()) {
 }
 
-Canvas::~Canvas() {
+Canvas::Canvas(SkCanvas* canvas, float image_scale)
+    : image_scale_(image_scale), owned_canvas_(), canvas_(canvas) {
+  DCHECK(canvas);
 }
 
-// static
-Canvas* Canvas::CreateCanvasWithoutScaling(SkCanvas* canvas,
-                                           float image_scale) {
-  return new Canvas(canvas, image_scale);
+Canvas::~Canvas() {
 }
 
 void Canvas::RecreateBackingCanvas(const Size& size,
@@ -544,13 +543,6 @@ void Canvas::Transform(const gfx::Transform& transform) {
   canvas_->concat(transform.matrix());
 }
 
-Canvas::Canvas(SkCanvas* canvas, float image_scale)
-    : image_scale_(image_scale),
-      owned_canvas_(),
-      canvas_(canvas) {
-  DCHECK(canvas);
-}
-
 bool Canvas::IntersectsClipRectInt(int x, int y, int w, int h) {
   SkRect clip;
   return canvas_->getClipBounds(&clip) &&