remove subclassing from ImageFilter::Proxy

src/core/SkImageFilter.cpp

Index: src/core/SkImageFilter.cpp
diff --git a/src/core/SkImageFilter.cpp b/src/core/SkImageFilter.cpp
index 91b3bc3d4afad1efc7da7a6e95ded8cf3752a82b..f5122040e951025261dec832a1016d3048429588 100644
--- a/src/core/SkImageFilter.cpp
+++ b/src/core/SkImageFilter.cpp
@@ -523,3 +523,26 @@ SkImageFilter::Cache* SkImageFilter::Cache::Get() {
 void SkImageFilter::PurgeCache() {
     cache.get()->purge();
 }
+
+///////////////////////////////////////////////////////////////////////////////////////////////////
+
+#include "SkBitmapDevice.h"

[Stephen White, 2015/06/09 15:17:04]

Nit: move this to top-of-file?

+
+SkBaseDevice* SkImageFilter::Proxy::createDevice(int w, int h) {
+    SkBaseDevice::CreateInfo cinfo(SkImageInfo::MakeN32Premul(w, h),

[robertphillips, 2015/06/09 17:07:29]

What about the SkTileImageFilter?

[Stephen White, 2015/06/10 14:42:45]

SkTileImageFilter always does an extractSubset() of its input, which I believe
makes it tiling-safe, even on GPU.

At any rate, this code is not new -- Mike just moved it here from
SkDeviceImageFilterProxy.

+                                   SkBaseDevice::kNever_TileUsage,
+                                   kUnknown_SkPixelGeometry,
+                                   true /*forImageFilter*/);
+    SkBaseDevice* dev = fDevice->onCreateDevice(cinfo, NULL);

[robertphillips, 2015/06/09 17:07:29]

!dev ?

+    if (NULL == dev) {
+        dev = SkBitmapDevice::Create(cinfo.fInfo);
+    }
+    return dev;
+}
+
+bool SkImageFilter::Proxy::filterImage(const SkImageFilter* filter, const SkBitmap& src,
+                                       const SkImageFilter::Context& ctx,
+                                       SkBitmap* result, SkIPoint* offset) {
+    return fDevice->filterImage(filter, src, ctx, result, offset);
+}
+