Use constexpr constructors of GrStencilSettings rather than hacky macro system

src/gpu/gl/GrGLGpu.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrGLGpu.h"
 #include "GrGLBuffer.h"
 #include "GrGLGLSL.h"
@@ skipping 2886 matching lines @@
     static const GrGLenum gTable[] = {
         GR_GL_KEEP,        // kKeep_StencilOp
         GR_GL_REPLACE,     // kReplace_StencilOp
         GR_GL_INCR_WRAP,   // kIncWrap_StencilOp
         GR_GL_INCR,        // kIncClamp_StencilOp
         GR_GL_DECR_WRAP,   // kDecWrap_StencilOp
         GR_GL_DECR,        // kDecClamp_StencilOp
         GR_GL_ZERO,        // kZero_StencilOp
         GR_GL_INVERT,      // kInvert_StencilOp
     };
-    GR_STATIC_ASSERT(SK_ARRAY_COUNT(gTable) == kStencilOpCount);
+    GR_STATIC_ASSERT(SK_ARRAY_COUNT(gTable) == kStencilOpCnt);
     GR_STATIC_ASSERT(0 == kKeep_StencilOp);
     GR_STATIC_ASSERT(1 == kReplace_StencilOp);
     GR_STATIC_ASSERT(2 == kIncWrap_StencilOp);
     GR_STATIC_ASSERT(3 == kIncClamp_StencilOp);
     GR_STATIC_ASSERT(4 == kDecWrap_StencilOp);
     GR_STATIC_ASSERT(5 == kDecClamp_StencilOp);
     GR_STATIC_ASSERT(6 == kZero_StencilOp);
     GR_STATIC_ASSERT(7 == kInvert_StencilOp);
-    SkASSERT((unsigned) op < kStencilOpCount);
+    SkASSERT((unsigned) op < kStencilOpCnt);
     return gTable[op];
 }
 
 void set_gl_stencil(const GrGLInterface* gl,
                     const GrStencilSettings& settings,
                     GrGLenum glFace,
                     GrStencilSettings::Face grFace) {
     GrGLenum glFunc = GrToGLStencilFunc(settings.func(grFace));
     GrGLenum glFailOp = gr_to_gl_stencil_op(settings.failOp(grFace));
     GrGLenum glPassOp = gr_to_gl_stencil_op(settings.passOp(grFace));
@@ skipping 1344 matching lines @@
         if (GR_GL_TEXTURE_EXTERNAL == glTexture->target() ||
             GR_GL_TEXTURE_RECTANGLE == glTexture->target()) {
             copyParams->fFilter = GrTextureParams::kNone_FilterMode;
             copyParams->fWidth = texture->width();
             copyParams->fHeight = texture->height();
             return true;
         }
     }
     return false;
 }