[C++] Fix assign_in_parens.mk
diff --git a/strutil.h b/strutil.h
index 2be0aef..d7c3785 100644
--- a/strutil.h
+++ b/strutil.h
@@ -100,6 +100,6 @@
 void AbsPath(StringPiece s, string* o);
 
 size_t FindOutsideParen(StringPiece s, char c);
-size_t FindColonOrEqualOutsideParen(StringPiece s);
+size_t FindTwoOutsideParen(StringPiece s, char c1, char c2);
 
 #endif  // STRUTIL_H_