Split up SkXfermode::asNewEffectOrCoeff() into asNewEffect(), asCoeff().

src/effects/SkArithmeticMode.cpp

Index: src/effects/SkArithmeticMode.cpp
diff --git a/src/effects/SkArithmeticMode.cpp b/src/effects/SkArithmeticMode.cpp
index 7c4428c8adf1e8a65d2bc36a1d78dfefb701785c..3c445ab4851cfea4285c54a99857ae34b65330c9 100644
--- a/src/effects/SkArithmeticMode.cpp
+++ b/src/effects/SkArithmeticMode.cpp
@@ -36,7 +36,7 @@ public:
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkArithmeticMode_scalar)
 
 #if SK_SUPPORT_GPU
-    virtual bool asNewEffectOrCoeff(GrEffectRef** effect, Coeff*, Coeff*, GrTexture* background) const SK_OVERRIDE;
+    virtual bool asNewEffect(GrEffectRef** effect, GrTexture* background) const SK_OVERRIDE;
 #endif
 
 private:
@@ -408,10 +408,7 @@ GrEffectRef* GrArithmeticEffect::TestCreate(SkRandom* rand,
 
 GR_DEFINE_EFFECT_TEST(GrArithmeticEffect);
 
-bool SkArithmeticMode_scalar::asNewEffectOrCoeff(GrEffectRef** effect,
-                                                 Coeff*,
-                                                 Coeff*,
-                                                 GrTexture* background) const {
+bool SkArithmeticMode_scalar::asNewEffect(GrEffectRef** effect, GrTexture* background) const {
     if (effect) {
         *effect = GrArithmeticEffect::Create(SkScalarToFloat(fK[0]),
                                              SkScalarToFloat(fK[1]),