Abstracted diffuse color map out of SkLightingShaderImpl into a generic SkShader

src/core/SkNormalSource.cpp

Index: src/core/SkNormalSource.cpp
diff --git a/src/core/SkNormalSource.cpp b/src/core/SkNormalSource.cpp
index 4dbe879036dfc742b5d37a4452087c4d7bc8f66a..3064885f490c96037fdf931ae014b77587b10ba8 100644
--- a/src/core/SkNormalSource.cpp
+++ b/src/core/SkNormalSource.cpp
@@ -180,7 +180,6 @@ sk_sp<GrFragmentProcessor> NormalMapSourceImpl::asFragmentProcessor(
                                                      const SkMatrix *localMatrix,
                                                      SkFilterQuality filterQuality,
                                                      SkSourceGammaTreatment gammaTreatment) const {
-
     sk_sp<GrFragmentProcessor> mapFP = fMapShader->asFragmentProcessor(context, viewM,
             localMatrix, filterQuality, gammaTreatment);