Add arb_texture_rectangle support properly in GLES3 shaders

src/gpu/glsl/GrGLSLCaps.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "GrGLSLCaps.h"
 
 #include "GrContextOptions.h"
 
 ////////////////////////////////////////////////////////////////////////////////////////////
 
 GrGLSLCaps::GrGLSLCaps(const GrContextOptions& options) {
     fGLSLGeneration = k330_GrGLSLGeneration;
 
     fDropsTileOnZeroDivide = false;
     fFBFetchSupport = false;
     fFBFetchNeedsCustomOutput = false;
     fBindlessTextureSupport = false;
     fUsesPrecisionModifiers = false;
     fCanUseAnyFunctionInShader = true;
     fCanUseMinAndAbsTogether = true;
     fMustForceNegatedAtanParamToFloat = false;
+    // Consistent with the default GLSL generation.
+    fRectangleTextureUseUnifiedTextureFunctionName = true;
     fVersionDeclString = nullptr;
     fShaderDerivativeExtensionString = nullptr;
     fFragCoordConventionsExtensionString = nullptr;
     fSecondaryOutputExtensionString = nullptr;
     fExternalTextureExtensionString = nullptr;
+    fRectangleTextureExtensionString = nullptr;
     fFBFetchColorName = nullptr;
     fFBFetchExtensionString = nullptr;
     fAdvBlendEqInteraction = kNotSupported_AdvBlendEqInteraction;
 }
 
 SkString GrGLSLCaps::dump() const {
     SkString r = INHERITED::dump();
 
     static const char* kAdvBlendEqInteractionStr[] = {
         "Not Supported",
@@ skipping 18 matching lines @@
     r.appendf("Must force negated atan param to float: %s\n", (fMustForceNegatedAtanParamToFloat ?
                                                                "YES" : "NO"));
     r.appendf("Advanced blend equation interaction: %s\n",
               kAdvBlendEqInteractionStr[fAdvBlendEqInteraction]);
     return r;
 }
 
 void GrGLSLCaps::onApplyOptionsOverrides(const GrContextOptions& options) {
 }