change SkClipOp to a class enum

BUG=skia:

Change-Id: I25dbe6d6b8666a2a0a7be7bdd2ae0b067868d14e
Reviewed-on: https://skia-review.googlesource.com/5718
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
diff --git a/samplecode/SampleFatBits.cpp b/samplecode/SampleFatBits.cpp
index 65c929c..c49cdad 100644
--- a/samplecode/SampleFatBits.cpp
+++ b/samplecode/SampleFatBits.cpp
@@ -15,6 +15,7 @@
 #include "SkUtils.h"
 #include "SkImage.h"
 #include "SkSurface.h"
+#include "SkClipOpPriv.h"
 
 #define FAT_PIXEL_COLOR     SK_ColorBLACK
 #define PIXEL_CENTER_SIZE   3