fix a bug in scrolling BitmapText gpu cached textblobs

src/gpu/GrAtlasTextContext.h

Index: src/gpu/GrAtlasTextContext.h
diff --git a/src/gpu/GrAtlasTextContext.h b/src/gpu/GrAtlasTextContext.h
index 1a24e809a34b10cc4a04ae89dbc8efe3eb49dea0..c0b8b000710705d45fefc113a339b8cf8b69eb29 100644
--- a/src/gpu/GrAtlasTextContext.h
+++ b/src/gpu/GrAtlasTextContext.h
@@ -193,10 +193,6 @@ private:
         SkTArray<BigGlyph> fBigGlyphs;
         Key fKey;
         SkMatrix fViewMatrix;
-#ifdef SK_DEBUG
-        mutable SkScalar fTotalXError;
-        mutable SkScalar fTotalYError;
-#endif
         SkColor fPaintColor;
         SkScalar fX;
         SkScalar fY;