[gtk+] quartz: fix build on 10.6 and below

[Matthias Clasen <matthiasc src gnome org>]

commit a703437796fefb44d4058cd36d6ba13abaab4725
Author: Marcus Karlsson <mk acc umu se>
Date:   Sun Oct 26 12:26:48 2014 +0100

    quartz: fix build on 10.6 and below
    
    It is not possible to successfully build GTK+ on OS X 10.6 and below
    since NSFullScreenWindowMask is only available starting with 10.7. Add
    ifdef guards around setStyleMask: in order to allow it to build on
    earlier OS X releases.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=737561

 gdk/quartz/GdkQuartzNSWindow.c |    4 ++++
 gdk/quartz/GdkQuartzNSWindow.h |    3 +++
 2 files changed, 7 insertions(+), 0 deletions(-)
---
diff --git a/gdk/quartz/GdkQuartzNSWindow.c b/gdk/quartz/GdkQuartzNSWindow.c
index 6bc05a4..43348ef 100644
--- a/gdk/quartz/GdkQuartzNSWindow.c
+++ b/gdk/quartz/GdkQuartzNSWindow.c
@@ -654,6 +654,8 @@ update_context_from_dragging_info (id <NSDraggingInfo> sender)
   _gdk_quartz_drag_source_context = NULL;
 }
 
+#ifdef AVAILABLE_MAC_OS_X_VERSION_10_7_AND_LATER
+
 - (void)setStyleMask:(NSUInteger)styleMask
 {
   gboolean was_fullscreen;
@@ -669,4 +671,6 @@ update_context_from_dragging_info (id <NSDraggingInfo> sender)
     _gdk_quartz_window_update_fullscreen_state ([[self contentView] gdkWindow]);
 }
 
+#endif
+
 @end
diff --git a/gdk/quartz/GdkQuartzNSWindow.h b/gdk/quartz/GdkQuartzNSWindow.h
index 80b910c..540b965 100644
--- a/gdk/quartz/GdkQuartzNSWindow.h
+++ b/gdk/quartz/GdkQuartzNSWindow.h
@@ -42,7 +42,10 @@
 -(BOOL)trackManualResize;
 -(void)showAndMakeKey:(BOOL)makeKey;
 -(void)hide;
+
+#ifdef AVAILABLE_MAC_OS_X_VERSION_10_7_AND_LATER
 -(void)setStyleMask:(NSUInteger)styleMask;
+#endif
 
 @end