Allow setting of GrBatchFontCache atlas sizes

src/gpu/GrBatchFontCache.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrBatchFontCache_DEFINED
 #define GrBatchFontCache_DEFINED
 
@@ skipping 148 matching lines @@
         return this->getAtlas(format)->addToAtlas(id, target, width, height, image, loc);
     }
 
     // Some clients may wish to verify the integrity of the texture backing store of the
     // GrBatchAtlas.  The atlasGeneration returned below is a monitonically increasing number which
     // changes everytime something is removed from the texture backing store.
     uint64_t atlasGeneration(GrMaskFormat format) const {
         return this->getAtlas(format)->atlasGeneration();
     }
 
+    ///////////////////////////////////////////////////////////////////////////
+    // Functions intended debug only
     void dump() const;
 
+    void setAtlasSizes_ForTesting(const GrBatchAtlasConfig configs[3]);
+
 private:
     static GrPixelConfig MaskFormatToPixelConfig(GrMaskFormat format) {
         static const GrPixelConfig kPixelConfigs[] = {
             kAlpha_8_GrPixelConfig,
             kRGB_565_GrPixelConfig,
             kSkia8888_GrPixelConfig
         };
         SK_COMPILE_ASSERT(SK_ARRAY_COUNT(kPixelConfigs) == kMaskFormatCount, array_size_mismatch);
 
         return kPixelConfigs[format];
@@ skipping 25 matching lines @@
         SkASSERT(fAtlases[atlasIndex]);
         return fAtlases[atlasIndex];
     }
 
     static void HandleEviction(GrBatchAtlas::AtlasID, void*);
 
     GrContext* fContext;
     SkTDynamicHash<GrBatchTextStrike, GrFontDescKey> fCache;
     GrBatchAtlas* fAtlases[kMaskFormatCount];
     GrBatchTextStrike* fPreserveStrike;
+    GrBatchAtlasConfig fAtlasConfigs[kMaskFormatCount];
 };
 
 #endif