Added API for Bevel NormalSource.

src/core/SkNormalSource.h

Index: src/core/SkNormalSource.h
diff --git a/src/core/SkNormalSource.h b/src/core/SkNormalSource.h
index 7517770800190e7bb851cba8886786ba129be07d..3933deaa90b25232e56f8e61c3721cb70396c893 100644
--- a/src/core/SkNormalSource.h
+++ b/src/core/SkNormalSource.h
@@ -65,6 +65,20 @@ public:
     */
     static sk_sp<SkNormalSource> MakeFromNormalMap(sk_sp<SkShader> map, const SkMatrix& ctm);
 
+    enum class BevelType {
+        kLinear,
+        kRoundedOut,
+        kRoundedIn
+    };
+    /** Returns a normal source that generates a bevel for the given shape. UNIMPLEMENTED: Will
+        return straight-up normals only.
+
+        @param  type   the type of bevel to add

[robertphillips, 2016/07/11 19:13:21]

Mention what space 'width' and 'height' are in. Source, right ?

[dvonbeck, 2016/07/13 14:23:38]

Yes. Done.

+        @param  width  the width of the bevel
+        @param  height the height of the plateau
+    */
+    static sk_sp<SkNormalSource> MakeBevel(BevelType, SkScalar width, SkScalar height);
+
     SK_DEFINE_FLATTENABLE_TYPE(SkNormalSource)
     SK_DECLARE_FLATTENABLE_REGISTRAR_GROUP()
 };