fix windows build (followup e0d20e53)

src/core/CMakeLists.txt

@@ -163,6 +163,7 @@ SET(QGIS_CORE_SRCS
   qgslegendstyle.cpp
   qgslocalec.cpp
   qgslogger.cpp
+  qgsmapdecoration.cpp
   qgsmaphittest.cpp
   qgsmaplayer.cpp
   qgsmaplayerlegend.cpp

src/core/qgsmapdecoration.cpp

@@ -0,0 +1,22 @@
+/***************************************************************************
+                          qgsmapdecoration.cpp
+                          ----------------
+    begin                : April 2017
+    copyright            : (C) 2017 by Mathieu Pellerin
+    email                : nirvn dot asia at gmail dot com
+ ***************************************************************************/
+
+/***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#include "qgsmapdecoration.h"
+
+QgsMapDecoration::QgsMapDecoration()
+{
+}

src/core/qgsmapdecoration.h

@@ -37,7 +37,7 @@ class CORE_EXPORT QgsMapDecoration
     /**
      * Constructor for QgsMapDecoration.
      */
-    QgsMapDecoration() {}
+    QgsMapDecoration();
 
     virtual ~QgsMapDecoration() = default;