Revert of SkRTConf: reduce functionality to what we use, increase simplicity

src/gpu/gl/GrGLGpuProgramCache.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 "builders/GrGLProgramBuilder.h"
 #include "GrProcessor.h"
 #include "GrGLPathRendering.h"
 #include "glsl/GrGLSLFragmentProcessor.h"
 #include "glsl/GrGLSLProgramDataManager.h"
 #include "glsl/GrGLSLProgramDesc.h"
+#include "SkRTConf.h"
 #include "SkTSearch.h"
 
 #ifdef PROGRAM_CACHE_STATS
-// Display program cache usage
-static const bool c_DisplayCache{false};
+SK_CONF_DECLARE(bool, c_DisplayCache, "gpu.displayCache", false,
+                "Display program cache usage.");
 #endif
 
 typedef GrGLSLProgramDataManager::UniformHandle UniformHandle;
 
 struct GrGLGpu::ProgramCache::Entry {
 
     Entry() : fProgram(nullptr), fLRUStamp(0) {}
 
     SkAutoTUnref<GrGLProgram>   fProgram;
     unsigned int                fLRUStamp;
@@ skipping 180 matching lines @@
 
     if (SK_MaxU32 == fCurrLRUStamp) {
         // wrap around! just trash our LRU, one time hit.
         for (int i = 0; i < fCount; ++i) {
             fEntries[i]->fLRUStamp = 0;
         }
     }
     ++fCurrLRUStamp;
     return SkRef(entry->fProgram.get());
 }