Initialize subrun variables to make Valgrind happy

src/gpu/GrAtlasTextBlob.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 GrAtlasTextBlob_DEFINED
 #define GrAtlasTextBlob_DEFINED
 
@@ skipping 59 matching lines @@
             // To ensure we always have one subrun, we push back a fresh run here
             fSubRunInfo.push_back();
         }
         struct SubRunInfo {
             SubRunInfo()
                 : fAtlasGeneration(GrBatchAtlas::kInvalidAtlasGeneration)
                 , fVertexStartIndex(0)
                 , fVertexEndIndex(0)
                 , fGlyphStartIndex(0)
                 , fGlyphEndIndex(0)
-                , fDrawAsDistanceFields(false) {}
+                , fTextRatio(1.0f)
+                , fMaskFormat(kA8_GrMaskFormat)
+                , fDrawAsDistanceFields(false)
+                , fUseLCDText(false) {}
             SubRunInfo(const SubRunInfo& that)
                 : fBulkUseToken(that.fBulkUseToken)
                 , fStrike(SkSafeRef(that.fStrike.get()))
                 , fAtlasGeneration(that.fAtlasGeneration)
                 , fVertexStartIndex(that.fVertexStartIndex)
                 , fVertexEndIndex(that.fVertexEndIndex)
                 , fGlyphStartIndex(that.fGlyphStartIndex)
                 , fGlyphEndIndex(that.fGlyphEndIndex)
                 , fTextRatio(that.fTextRatio)
                 , fMaskFormat(that.fMaskFormat)
@@ skipping 147 matching lines @@
     void setHasDistanceField() { fTextType |= kHasDistanceField_TextType; }
     void setHasBitmap() { fTextType |= kHasBitmap_TextType; }
 
 #ifdef CACHE_SANITY_CHECK
     static void AssertEqual(const GrAtlasTextBlob&, const GrAtlasTextBlob&);
     size_t fSize;
 #endif
 };
 
 #endif