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/samplecode/SampleBigBlur.cpp b/samplecode/SampleBigBlur.cpp
index 928fc6f..fcbd6ac 100644
--- a/samplecode/SampleBigBlur.cpp
+++ b/samplecode/SampleBigBlur.cpp
@@ -31,7 +31,7 @@
         canvas->save();
         paint.setColor(SK_ColorBLUE);
         SkMaskFilter* mf = SkBlurMaskFilter::Create(
-            SkBlurMaskFilter::kNormal_BlurStyle,
+            kNormal_SkBlurStyle,
             SkBlurMask::ConvertRadiusToSigma(SkIntToScalar(128)),
             SkBlurMaskFilter::kHighQuality_BlurFlag);
         paint.setMaskFilter(mf)->unref();