Clean up GrGLSLFragmentProcessor-derived classes

src/effects/SkPixelXorXfermode.cpp

Index: src/effects/SkPixelXorXfermode.cpp
diff --git a/src/effects/SkPixelXorXfermode.cpp b/src/effects/SkPixelXorXfermode.cpp
index 2eb42942cdd9a0db6262dba863ae83a252615eb4..833eecd85940f4fd6c37856d863d2edb691f04dc 100644
--- a/src/effects/SkPixelXorXfermode.cpp
+++ b/src/effects/SkPixelXorXfermode.cpp
@@ -171,10 +171,6 @@ private:
 
 class GLPixelXorFP : public GrGLSLFragmentProcessor {
 public:
-    GLPixelXorFP(const PixelXorFP&) {}
-
-    ~GLPixelXorFP() override {}
-
     void emitCode(EmitArgs& args) override {
         GrGLSLFragmentBuilder* fragBuilder = args.fFragBuilder;
         SkString dstColor("dstColor");
@@ -209,7 +205,7 @@ private:
 ///////////////////////////////////////////////////////////////////////////////
 
 GrGLSLFragmentProcessor* PixelXorFP::onCreateGLSLInstance() const {
-    return new GLPixelXorFP(*this);
+    return new GLPixelXorFP;
 }
 
 void PixelXorFP::onGetGLSLProcessorKey(const GrGLSLCaps& caps, GrProcessorKeyBuilder* b) const {