cc: Renamed approximate{BytesUsed,OpCount} in paint op buffer.

cc/paint/filter_display_item.h

Index: cc/paint/filter_display_item.h
diff --git a/cc/paint/filter_display_item.h b/cc/paint/filter_display_item.h
index c4f18dcbc85cbf1a57bcbd8ae8244384e4a0a949..ad40ff977e28433927ac9ed49986f807a36b1b6b 100644
--- a/cc/paint/filter_display_item.h
+++ b/cc/paint/filter_display_item.h
@@ -25,7 +25,7 @@ class CC_PAINT_EXPORT FilterDisplayItem : public DisplayItem {
     // enough.
     return filters.size() * sizeof(filters.at(0));
   }
-  int ApproximateOpCount() const { return 1; }
+  int OpCount() const { return 1; }
 
   const FilterOperations filters;
   const gfx::RectF bounds;
@@ -37,7 +37,7 @@ class CC_PAINT_EXPORT EndFilterDisplayItem : public DisplayItem {
   EndFilterDisplayItem();
   ~EndFilterDisplayItem() override;
 
-  int ApproximateOpCount() const { return 0; }
+  int OpCount() const { return 0; }
 };
 
 }  // namespace cc