[pangomm] Fix compilation of each header file

[Kjell Ahlstedt <kjellahl src gnome org>]

commit 7d050892e4afff00304c0bc66c60bfc8e84a3207
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Mon Sep 3 17:11:34 2018 +0200

    Fix compilation of each header file
    
    Add #includes, necessary to make all header files pass the test with
    glibmm/tools/test_scripts/testheaders.sh.

 pango/src/coverage.hg   | 3 +--
 pango/src/layoutline.hg | 3 +--
 2 files changed, 2 insertions(+), 4 deletions(-)
---
diff --git a/pango/src/coverage.hg b/pango/src/coverage.hg
index bc18390..9506b91 100644
--- a/pango/src/coverage.hg
+++ b/pango/src/coverage.hg
@@ -1,5 +1,3 @@
-/* $Id: coverage.hg,v 1.1 2003/01/21 13:41:03 murrayc Exp $ */
-
 /* coverage.h
  *
  * Copyright (C) 1998-1999 The gtkmm Development Team
@@ -19,6 +17,7 @@
  * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include <glibmm/value.h>
 #include <pango/pango-font.h>
 
 _DEFS(pangomm,pango)
diff --git a/pango/src/layoutline.hg b/pango/src/layoutline.hg
index 646b09d..6134556 100644
--- a/pango/src/layoutline.hg
+++ b/pango/src/layoutline.hg
@@ -1,5 +1,3 @@
-/* $Id: layoutline.hg,v 1.5 2006/05/30 17:14:21 murrayc Exp $ */
-
 /* layoutline.h
  *
  * Copyright (C) 1998-1999 The gtkmm Development Team
@@ -19,6 +17,7 @@
  * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include <glibmm/refptr.h>
 #include <pangomm/rectangle.h>
 #include <cairomm/context.h>
 #include <pango/pango-layout.h>