Rename paint data structures

cc/paint/paint_canvas.cc

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "cc/paint/paint_canvas.h"
+
+namespace cc {
+
+PaintCanvasPassThrough::PaintCanvasPassThrough(SkCanvas* canvas)
+    : SkNWayCanvas(canvas->getBaseLayerSize().width(),
+                   canvas->getBaseLayerSize().height()) {
+  SkIRect raster_bounds;
+  canvas->getDeviceClipBounds(&raster_bounds);
+  clipRect(SkRect::MakeFromIRect(raster_bounds));
+  setMatrix(canvas->getTotalMatrix());
+  addCanvas(canvas);
+}
+
+PaintCanvasPassThrough::PaintCanvasPassThrough(int width, int height)
+    : SkNWayCanvas(width, height) {}
+
+PaintCanvasPassThrough::~PaintCanvasPassThrough() = default;
+
+}  // namespace cc