paint: Introduce PaintImage that wraps SkImage in paint calls.

cc/paint/paint_image.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_image.h"
+
+namespace cc {
+
+PaintImage::PaintImage(sk_sp<const SkImage> sk_image,
+                       AnimationType animation_type,
+                       CompletionState completion_state)
+    : sk_image_(std::move(sk_image)),
+      animation_type_(animation_type),
+      completion_state_(completion_state) {}
+PaintImage::~PaintImage() = default;
+
+}  // namespace cc