Replace a lot of 'static const' with 'constexpr' or 'const'.

gm/lightingshader2.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "gm.h"
 #include "SkLightingShader.h"
 #include "SkNormalSource.h"
@@ skipping 236 matching lines @@
             canvas->save();
             canvas->translate(xPos, yPos);
             this->drawRect(canvas, 1.0f, 1.0f, 0.0f, true, true, false, false, fLightsTwoDir);
             canvas->restore();
 
             gridNum++;
         }
     }
 
 private:
-    static const int kTexSize = 96;
+    static constexpr int kTexSize = 96;
 
     sk_sp<SkShader> fOpaqueDiffuse;
     sk_sp<SkShader> fTranslucentDiffuse;
     sk_sp<SkShader> fNormalMapShader;
 
     SkRect fRect;
     sk_sp<SkLights> fLights;
     sk_sp<SkLights> fLightsNoDir;
     sk_sp<SkLights> fLightsTwoDir;
 
     typedef GM INHERITED;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
 DEF_GM(return new LightingShader2GM;)
 }