re-re-land of skslc now automatically turns on derivatives support

src/gpu/effects/GrDistanceFieldGeoProc.cpp

Index: src/gpu/effects/GrDistanceFieldGeoProc.cpp
diff --git a/src/gpu/effects/GrDistanceFieldGeoProc.cpp b/src/gpu/effects/GrDistanceFieldGeoProc.cpp
index 5404b0c80570cecf5255132f23c0edfdd7f3fd28..7f9fd85e6b621a841827d41140d9e07851738640 100644
--- a/src/gpu/effects/GrDistanceFieldGeoProc.cpp
+++ b/src/gpu/effects/GrDistanceFieldGeoProc.cpp
@@ -35,8 +35,6 @@ public:
         const GrDistanceFieldA8TextGeoProc& dfTexEffect =
                 args.fGP.cast<GrDistanceFieldA8TextGeoProc>();
         GrGLSLPPFragmentBuilder* fragBuilder = args.fFragBuilder;
-        SkAssertResult(fragBuilder->enableFeature(
-                GrGLSLFragmentShaderBuilder::kStandardDerivatives_GLSLFeature));
 
         GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
         GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
@@ -313,8 +311,6 @@ public:
         const GrDistanceFieldPathGeoProc& dfTexEffect = args.fGP.cast<GrDistanceFieldPathGeoProc>();
 
         GrGLSLPPFragmentBuilder* fragBuilder = args.fFragBuilder;
-        SkAssertResult(fragBuilder->enableFeature(
-                                     GrGLSLFragmentShaderBuilder::kStandardDerivatives_GLSLFeature));
 
         GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
         GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
@@ -610,9 +606,6 @@ public:
 
         // add frag shader code
 
-        SkAssertResult(fragBuilder->enableFeature(
-                GrGLSLFragmentShaderBuilder::kStandardDerivatives_GLSLFeature));
-
         // create LCD offset adjusted by inverse of transform
         // Use highp to work around aliasing issues
         fragBuilder->appendPrecisionModifier(kHigh_GrSLPrecision);