Deprecate SkDevice::accessBitmap method

Relies on https://codereview.chromium.org/2162423003/ (Add SK_SUPPORT_LEGACY_ACCESSBITMAP Skia guard) landing in Chromium first.

Calved off: https://codereview.chromium.org/2163323002/ (Add desired width & height to drawContext (as opposed to using the width & height of the RT))

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2168483003

Review-Url: https://codereview.chromium.org/2168483003
diff --git a/src/svg/SkSVGDevice.h b/src/svg/SkSVGDevice.h
index 3323471..bf86e15 100644
--- a/src/svg/SkSVGDevice.h
+++ b/src/svg/SkSVGDevice.h
@@ -55,7 +55,6 @@
 
     void drawDevice(const SkDraw&, SkBaseDevice*, int x, int y,
                     const SkPaint&) override;
-    const SkBitmap& onAccessBitmap() override;
 
 private:
     SkSVGDevice(const SkISize& size, SkXMLWriter* writer);
@@ -69,7 +68,7 @@
     SkXMLWriter*                  fWriter;
     SkAutoTDelete<AutoElement>    fRootElement;
     SkAutoTDelete<ResourceBucket> fResourceBucket;
-    SkBitmap                      fLegacyBitmap;
+    SkISize                       fSize;
 
     typedef SkBaseDevice INHERITED;
 };