StaticImageBitmap::create should return PassRefPtr<StaticImageBitmap>

instead of PassRefPtr<Image>

Also, move the implementation of "imageForCurrentFrame()" to .cpp file.

Review URL: https://codereview.chromium.org/1460653003

Cr-Commit-Position: refs/heads/master@{#360493}

third_party/WebKit/Source/platform/graphics/StaticBitmapImage.cpp

@@ -14,7 +14,7 @@
 
 namespace blink {
 
-PassRefPtr<Image> StaticBitmapImage::create(PassRefPtr<SkImage> image)
+PassRefPtr<StaticBitmapImage> StaticBitmapImage::create(PassRefPtr<SkImage> image)
 {
     if (!image)
         return nullptr;
@@ -60,4 +60,9 @@ void StaticBitmapImage::draw(SkCanvas* canvas, const SkPaint& paint, const Float
         observer->didDraw(this);
 }
 
+PassRefPtr<SkImage> StaticBitmapImage::imageForCurrentFrame()
+{
+    return m_image;
+}
+
 } // namespace blink

third_party/WebKit/Source/platform/graphics/StaticBitmapImage.h

@@ -15,13 +15,13 @@ public:
 
     bool currentFrameIsComplete() override { return true; }
 
-    static PassRefPtr<Image> create(PassRefPtr<SkImage>);
+    static PassRefPtr<StaticBitmapImage> create(PassRefPtr<SkImage>);
     virtual void destroyDecodedData(bool destroyAll) { }
     virtual bool currentFrameKnownToBeOpaque();
     virtual IntSize size() const;
     void draw(SkCanvas*, const SkPaint&, const FloatRect& dstRect, const FloatRect& srcRect, RespectImageOrientationEnum, ImageClampingMode) override;
 
-    PassRefPtr<SkImage> imageForCurrentFrame() override { return m_image; }
+    PassRefPtr<SkImage> imageForCurrentFrame() override;
 
 protected:
     StaticBitmapImage(PassRefPtr<SkImage>);