Replace SkTLazy with base::Optional

cc/playback/image_hijack_canvas.cc

 // Copyright 2016 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/playback/image_hijack_canvas.h"
 
+#include "base/optional.h"
 #include "cc/playback/discardable_image_map.h"
 #include "cc/tiles/image_decode_controller.h"
-#include "third_party/skia/include/core/SkTLazy.h"
 
 namespace cc {
 namespace {
 
 SkIRect RoundOutRect(const SkRect& rect) {
   SkIRect result;
   rect.roundOut(&result);
   return result;
 }
 
 class ScopedDecodedImageLock {
  public:
   ScopedDecodedImageLock(ImageDecodeController* image_decode_controller,
                          sk_sp<const SkImage> image,
                          const SkRect& src_rect,
                          const SkMatrix& matrix,
                          const SkPaint* paint)
       : image_decode_controller_(image_decode_controller),
         draw_image_(std::move(image),
                     RoundOutRect(src_rect),
                     paint ? paint->getFilterQuality() : kNone_SkFilterQuality,
                     matrix),
         decoded_draw_image_(
             image_decode_controller_->GetDecodedImageForDraw(draw_image_)) {
     DCHECK(draw_image_.image()->isLazyGenerated());
-    if (paint)
-      decoded_paint_.set(*paint)->setFilterQuality(
-          decoded_draw_image_.filter_quality());
+    if (paint) {
+      decoded_paint_ = *paint;
+      decoded_paint_->setFilterQuality(decoded_draw_image_.filter_quality());
+    }
   }
 
   ~ScopedDecodedImageLock() {
     image_decode_controller_->DrawWithImageFinished(draw_image_,
                                                     decoded_draw_image_);
   }
 
   const DecodedDrawImage& decoded_image() const { return decoded_draw_image_; }
-  const SkPaint* decoded_paint() const { return decoded_paint_.getMaybeNull(); }
+  const SkPaint* decoded_paint() const {
+    return decoded_paint_ ? &(*decoded_paint_) : nullptr;

[bungeman-chromium, 2016/04/27 19:59:34]

danakj wanted this to just look like &*decoded_paint_, this could also be
&decoded_paint_.value() since for base::Optional that's the same operation. I
find this second form a bit clearer, since it makes it obvious that one is
taking the address of the value and not the decoded_paint_ field itself.

+  }
 
  private:
   ImageDecodeController* image_decode_controller_;
   DrawImage draw_image_;
   DecodedDrawImage decoded_draw_image_;
-  // TODO(fmalita): use base::Optional when it becomes available
-  SkTLazy<SkPaint> decoded_paint_;
+  base::Optional<SkPaint> decoded_paint_;
 };
 
 }  // namespace
 
 ImageHijackCanvas::ImageHijackCanvas(
     int width,
     int height,
     ImageDecodeController* image_decode_controller)
     : SkNWayCanvas(width, height),
       image_decode_controller_(image_decode_controller) {}
@@ skipping 82 matching lines @@
 
 void ImageHijackCanvas::onDrawImageNine(const SkImage* image,
                                         const SkIRect& center,
                                         const SkRect& dst,
                                         const SkPaint* paint) {
   // No cc embedder issues image nine calls.
   NOTREACHED();
 }
 
 }  // namespace cc