Add can-ignore-rect hint to clear call

src/gpu/GrInOrderDrawBuffer.h

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrInOrderDrawBuffer_DEFINED
 #define GrInOrderDrawBuffer_DEFINED
 
@@ skipping 53 matching lines @@
     void flush();
 
     // tracking for draws
     virtual DrawToken getCurrentDrawToken() { return DrawToken(this, fDrawID); }
 
     // overrides from GrDrawTarget
     virtual bool geometryHints(int* vertexCount,
                                int* indexCount) const SK_OVERRIDE;
     virtual void clear(const SkIRect* rect,
                        GrColor color,
+                       bool canIgnoreRect,
                        GrRenderTarget* renderTarget = NULL) SK_OVERRIDE;
 
     virtual void initCopySurfaceDstDesc(const GrSurface* src, GrTextureDesc* desc) SK_OVERRIDE;
 
 protected:
     virtual void clipWillBeSet(const GrClipData* newClip) SK_OVERRIDE;
 
 private:
     enum Cmd {
         kDraw_Cmd           = 1,
@@ skipping 26 matching lines @@
         SkPath::FillType            fFill;
         GrDeviceCoordTexture        fDstCopy;
     };
 
     struct Clear : public ::SkNoncopyable {
         Clear() : fRenderTarget(NULL) {}
         ~Clear() { SkSafeUnref(fRenderTarget); }
 
         SkIRect         fRect;
         GrColor         fColor;
+        bool            fCanIgnoreRect;
         GrRenderTarget* fRenderTarget;
     };
 
     struct CopySurface : public ::SkNoncopyable {
         SkAutoTUnref<GrSurface> fDst;
         SkAutoTUnref<GrSurface> fSrc;
         SkIRect                 fSrcRect;
         SkIPoint                fDstPoint;
     };
 
@@ skipping 108 matching lines @@
 
     virtual bool       isIssued(uint32_t drawID) { return drawID != fDrawID; }
 
     bool                            fFlushing;
     uint32_t                        fDrawID;
 
     typedef GrDrawTarget INHERITED;
 };
 
 #endif