SSE2 implementation of RGBA box blurs. This yields ~2X perf improvement on

src/opts/opts_check_SSE2.cpp

 /*
  * Copyright 2009 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmapProcState_opts_SSE2.h"
 #include "SkBitmapProcState_opts_SSSE3.h"
 #include "SkBitmapFilter_opts_SSE2.h"
 #include "SkBlitMask.h"
 #include "SkBlitRow.h"
 #include "SkBlitRect_opts_SSE2.h"
 #include "SkBlitRow_opts_SSE2.h"
+#include "SkBlurImage_opts_SSE2.h"
 #include "SkUtils_opts_SSE2.h"
 #include "SkUtils.h"
 #include "SkMorphology_opts.h"
 #include "SkMorphology_opts_SSE2.h"
 
 #include "SkRTConf.h"
 
 #if defined(_MSC_VER) && defined(_WIN64)
 #include <intrin.h>
 #endif
@@ skipping 236 matching lines @@
             return SkDilateY_SSE2;
         case kErodeX_SkMorphologyProcType:
             return SkErodeX_SSE2;
         case kErodeY_SkMorphologyProcType:
             return SkErodeY_SSE2;
         default:
             return NULL;
     }
 }
 
+bool SkBoxBlurGetPlatformProcs(SkBoxBlurProc* boxBlurX,
+                               SkBoxBlurProc* boxBlurY,
+                               SkBoxBlurProc* boxBlurXY) {
+#ifdef SK_DISABLE_BLUR_DIVISION_OPTIMIZATION
+    return false;
+#else
+    if (!cachedHasSSE2()) {
+        return false;
+    }
+    return SkBoxBlurGetPlatformProcs_SSE2(boxBlurX, boxBlurY, boxBlurXY);
+#endif
+}
+
 SkBlitRow::ColorRectProc PlatformColorRectProcFactory(); // suppress warning
 
 SkBlitRow::ColorRectProc PlatformColorRectProcFactory() {
     if (cachedHasSSE2()) {
         return ColorRect32_SSE2;
     } else {
         return NULL;
     }
 }