move common blur types into central header

BUG=skia:
R=scroggo@google.com, djsollen@google.com

Author: reed@google.com

Review URL: https://codereview.chromium.org/253833002

git-svn-id: http://skia.googlecode.com/svn/trunk@14411 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/bench/RectoriBench.cpp b/bench/RectoriBench.cpp
index 87f5fee..84af352 100644
--- a/bench/RectoriBench.cpp
+++ b/bench/RectoriBench.cpp
@@ -85,7 +85,7 @@
 
         SkPaint* paint = looperBuilder.addLayer(info);
 
-        SkMaskFilter* mf = SkBlurMaskFilter::Create(SkBlurMaskFilter::kNormal_BlurStyle,
+        SkMaskFilter* mf = SkBlurMaskFilter::Create(kNormal_SkBlurStyle,
                                                     sigma,
                                                     SkBlurMaskFilter::kHighQuality_BlurFlag);
         paint->setMaskFilter(mf)->unref();