Revert of Remove PaintCanvas::getBaseLayerSize.

cc/paint/paint_canvas.h

 // 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.
 
 #ifndef CC_PAINT_PAINT_CANVAS_H_
 #define CC_PAINT_PAINT_CANVAS_H_
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
@@ skipping 16 matching lines @@
   virtual SkImageInfo imageInfo() const = 0;
 
   // TODO(enne): It would be nice to get rid of flush() entirely, as it
   // doesn't really make sense for recording.  However, this gets used by
   // SkCanvasVideoRenderer which takes a PaintCanvas to paint both
   // software and hardware video.  This is super entangled with ImageBuffer
   // and canvas/video painting in Blink where the same paths are used for
   // both recording and gpu work.
   virtual void flush() = 0;
 
+  virtual SkISize getBaseLayerSize() const = 0;
   virtual bool writePixels(const SkImageInfo& info,
                            const void* pixels,
                            size_t row_bytes,
                            int x,
                            int y) = 0;
   virtual int save() = 0;
   virtual int saveLayer(const SkRect* bounds, const PaintFlags* flags) = 0;
   virtual int saveLayerAlpha(const SkRect* bounds, U8CPU alpha) = 0;
 
   virtual void restore() = 0;
@@ skipping 187 matching lines @@
 // Following routines are used in print preview workflow to mark the
 // preview metafile.
 #if defined(OS_MACOSX)
 CC_PAINT_EXPORT void SetIsPreviewMetafile(PaintCanvas* canvas, bool is_preview);
 CC_PAINT_EXPORT bool IsPreviewMetafile(PaintCanvas* canvas);
 #endif
 
 }  // namespace cc
 
 #endif  // CC_PAINT_PAINT_CANVAS_H_