Added tree structure to GrGLFragmentProcessor, i.e. GL instances

src/gpu/effects/GrMatrixConvolutionEffect.h

Index: src/gpu/effects/GrMatrixConvolutionEffect.h
diff --git a/src/gpu/effects/GrMatrixConvolutionEffect.h b/src/gpu/effects/GrMatrixConvolutionEffect.h
index ff0a51ea12918f17b36f76701fc402d56db9af95..f3d6b2461dacb2db5605db51f5a0b375f2dc0e51 100644
--- a/src/gpu/effects/GrMatrixConvolutionEffect.h
+++ b/src/gpu/effects/GrMatrixConvolutionEffect.h
@@ -65,8 +65,6 @@ public:
 
     const char* name() const override { return "MatrixConvolution"; }
 
-    GrGLFragmentProcessor* createGLInstance() const override;
-
 private:
     GrMatrixConvolutionEffect(GrProcessorDataManager*,
                               GrTexture*,
@@ -79,6 +77,8 @@ private:
                               GrTextureDomain::Mode tileMode,
                               bool convolveAlpha);
 
+    GrGLFragmentProcessor* onCreateGLInstance() const override;
+
     void onGetGLProcessorKey(const GrGLSLCaps&, GrProcessorKeyBuilder*) const override;
 
     bool onIsEqual(const GrFragmentProcessor&) const override;