Revert of Revert of Fix SkTileImageFilter clipping/cropRect interaction issue

include/core/SkImageFilter.h

Index: include/core/SkImageFilter.h
diff --git a/include/core/SkImageFilter.h b/include/core/SkImageFilter.h
index 911b3f648d5d6ae2e4c8cfd51dae55efcdffa40e..2b99376819d225d249a94a200f76ac9915b2272d 100644
--- a/include/core/SkImageFilter.h
+++ b/include/core/SkImageFilter.h
@@ -46,6 +46,9 @@
         explicit CropRect(const SkRect& rect, uint32_t flags = kHasAll_CropEdge) : fRect(rect), fFlags(flags) {}
         uint32_t flags() const { return fFlags; }
         const SkRect& rect() const { return fRect; }
+#ifndef SK_IGNORE_TO_STRING
+        void toString(SkString* str) const;
+#endif
     private:
         SkRect fRect;
         uint32_t fFlags;