Add GrShaderFlags enum

src/effects/SkAvoidXfermode.cpp

Index: src/effects/SkAvoidXfermode.cpp
diff --git a/src/effects/SkAvoidXfermode.cpp b/src/effects/SkAvoidXfermode.cpp
index 43d80c981038a095de050b3fe718f0c949816740..4edb100a40473e92bf4f3c0748dc8a4882637bc5 100644
--- a/src/effects/SkAvoidXfermode.cpp
+++ b/src/effects/SkAvoidXfermode.cpp
@@ -277,7 +277,7 @@ public:
         this->emitChild(0, nullptr, &dstColor, args);
 
         fColorAndTolUni = args.fUniformHandler->addUniform(
-                                                 GrGLSLUniformHandler::kFragment_Visibility,
+                                                 kFragment_GrShaderFlag,
                                                  kVec4f_GrSLType, kDefault_GrSLPrecision,
                                                  "colorAndTol");
         const char* kColorAndTolUni = args.fUniformHandler->getUniformCStr(fColorAndTolUni);
@@ -413,7 +413,7 @@ private:
                                  const GrXferProcessor& proc) override {
         const AvoidXP& avoid = proc.cast<AvoidXP>();
 
-        fColorAndTolUni = uniformHandler->addUniform(GrGLSLUniformHandler::kFragment_Visibility,
+        fColorAndTolUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                                      kVec4f_GrSLType, kDefault_GrSLPrecision,
                                                      "colorAndTol");
         const char* kColorandTolUni = uniformHandler->getUniformCStr(fColorAndTolUni);