Use unorm shorts for texture coordinates when rendering text.

src/gpu/text/GrBatchFontCache.h

Index: src/gpu/text/GrBatchFontCache.h
diff --git a/src/gpu/text/GrBatchFontCache.h b/src/gpu/text/GrBatchFontCache.h
index 46ab1c82741a2820f00fdc36358f2e8b17c549c7..7ff1b9e77ff868f2021d3afa6ec010fd48545472 100644
--- a/src/gpu/text/GrBatchFontCache.h
+++ b/src/gpu/text/GrBatchFontCache.h
@@ -171,6 +171,9 @@ public:
         return this->getAtlas(format)->atlasGeneration();
     }
 
+    int log2Width(GrMaskFormat format) { return fAtlasConfigs[format].fLog2Width; }
+    int log2Height(GrMaskFormat format) { return fAtlasConfigs[format].fLog2Height; }
+
     ///////////////////////////////////////////////////////////////////////////
     // Functions intended debug only
     void dump() const;