Rename GrAtlasTextContext -> GrTextContext

Change-Id: I309b39425afc9b45095241eeb299096bc426afed
Reviewed-on: https://skia-review.googlesource.com/130029
Reviewed-by: Herb Derby <herb@google.com>
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Herb Derby <herb@google.com>
diff --git a/include/core/SkPaint.h b/include/core/SkPaint.h
index 85c2e3b..6c60fc3 100644
--- a/include/core/SkPaint.h
+++ b/include/core/SkPaint.h
@@ -1678,7 +1678,7 @@
     static SkScalar MaxCacheSize2(SkScalar maxLimit);
 
     friend class GrAtlasTextBlob;
-    friend class GrAtlasTextContext;
+    friend class GrTextContext;
     friend class GrGLPathRendering;
     friend class GrPathRendering;
     friend class GrTextUtils;