Revert of Refactor how we store and use samplers in Ganesh

src/gpu/gl/GrGLSampler.h

-/*
-* Copyright 2016 Google Inc.
-*
-* Use of this source code is governed by a BSD-style license that can be
-* found in the LICENSE file.
-*/
-
-#ifndef GrGLSampler_DEFINED
-#define GrGLSampler_DEFINED
-
-#include "glsl/GrGLSLSampler.h"
-
-#include "gl/GrGLTypes.h"
-#include "glsl/GrGLSLShaderVar.h"
-
-class GrGLSampler : public GrGLSLSampler {
-public:
-    GrGLSampler(uint32_t visibility,
-                GrPixelConfig config,
-                GrSLType type,
-                GrSLPrecision precision,
-                const char* name) : INHERITED(visibility, config) {
-        SkASSERT(GrSLTypeIsSamplerType(type));
-        fShaderVar.setType(type);
-        fShaderVar.setTypeModifier(GrGLSLShaderVar::kUniform_TypeModifier);
-        fShaderVar.setPrecision(precision);
-        fShaderVar.accessName()->set(name);
-    }
-
-    GrGLint location() const { return fLocation; }
-    GrSLType type() const override { return fShaderVar.getType(); }
-
-    const char* onGetSamplerNameForTexture2D() const override { return fShaderVar.c_str(); }
-    const char* getSamplerNameForTexelFetch() const override { return fShaderVar.c_str(); }
-
-private:
-    GrGLSLShaderVar fShaderVar;
-    GrGLint         fLocation;
-
-    friend class GrGLUniformHandler;
-
-    typedef GrGLSLSampler INHERITED;
-};
-
-#endif