Image Filters: refactor all CPU input processing into a filterInput helper function.

src/core/SkLocalMatrixImageFilter.cpp

Index: src/core/SkLocalMatrixImageFilter.cpp
diff --git a/src/core/SkLocalMatrixImageFilter.cpp b/src/core/SkLocalMatrixImageFilter.cpp
index 17ee1028a8fe66ccc26360cf2d0ba55b06e76534..10d63ede66ed3b3c55e52fb691fe8b372e955dcd 100644
--- a/src/core/SkLocalMatrixImageFilter.cpp
+++ b/src/core/SkLocalMatrixImageFilter.cpp
@@ -41,7 +41,7 @@ void SkLocalMatrixImageFilter::flatten(SkWriteBuffer& buffer) const {
 bool SkLocalMatrixImageFilter::onFilterImage(Proxy* proxy, const SkBitmap& src, const Context& ctx,
                                              SkBitmap* result, SkIPoint* offset) const {
     Context localCtx(SkMatrix::Concat(ctx.ctm(), fLocalM), ctx.clipBounds(), ctx.cache());
-    return this->getInput(0)->filterImage(proxy, src, localCtx, result, offset);
+    return this->filterInput(0, proxy, src, localCtx, result, offset);
 }
 
 bool SkLocalMatrixImageFilter::onFilterBounds(const SkIRect& src, const SkMatrix& matrix,