Dont try to draw glyphs with unexpected mask formats

src/gpu/GrBatchFontCache.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrBatchFontCache.h"
 #include "GrContext.h"
 #include "GrFontAtlasSizes.h"
@@ skipping 178 matching lines @@
         if (id == (*iter).fID) {
             (*iter).fID = GrBatchAtlas::kInvalidAtlasID;
             fAtlasedGlyphs--;
             SkASSERT(fAtlasedGlyphs >= 0);
         }
         ++iter;
     }
 }
 
 bool GrBatchTextStrike::addGlyphToAtlas(GrBatchTarget* batchTarget, GrGlyph* glyph,
-                                        GrFontScaler* scaler, const SkGlyph& skGlyph) {
+                                        GrFontScaler* scaler, const SkGlyph& skGlyph,
+                                        GrMaskFormat expectedMaskFormat) {
     SkASSERT(glyph);
     SkASSERT(scaler);
     SkASSERT(fCache.find(glyph->fPackedID));
     SkASSERT(NULL == glyph->fPlot);
 
     SkAutoUnref ar(SkSafeRef(scaler));
 
-    int bytesPerPixel = GrMaskFormatBytesPerPixel(glyph->fMaskFormat);
+    int bytesPerPixel = GrMaskFormatBytesPerPixel(expectedMaskFormat);
 
     size_t size = glyph->fBounds.area() * bytesPerPixel;
     SkAutoSMalloc<1024> storage(size);
 
     if (GrGlyph::kDistance_MaskStyle == GrGlyph::UnpackMaskStyle(glyph->fPackedID)) {
         if (!scaler->getPackedGlyphDFImage(skGlyph, glyph->width(), glyph->height(),
                                            storage.get())) {
             return false;
         }
     } else {
         if (!scaler->getPackedGlyphImage(skGlyph, glyph->width(), glyph->height(),
-                                         glyph->width() * bytesPerPixel, storage.get())) {
+                                         glyph->width() * bytesPerPixel, expectedMaskFormat,
+                                         storage.get())) {
             return false;
         }
     }
 
-    bool success = fBatchFontCache->addToAtlas(this, &glyph->fID, batchTarget, glyph->fMaskFormat,
+    bool success = fBatchFontCache->addToAtlas(this, &glyph->fID, batchTarget, expectedMaskFormat,
                                                glyph->width(), glyph->height(),
                                                storage.get(), &glyph->fAtlasLocation);
     if (success) {
         fAtlasedGlyphs++;
     }
     return success;
 }