In case of an offscreen window find its onscreen embedder, and NULL
any GdkWindowImpl that's not quartz, checking all return values.
This replaces 16ded683, removing its unnecessary search_for_nearest
functions.
Any unchecked cast of a GdkWindowImpl to GdkWindowImplQuartz risks at
least getting an invalid member reference, not just the ones in
gdk_quartz_window_get_foo, and all calls to gdk_quartz_window_get_foo need
to be checked, not just Gtk's internal calls. The motivation was that
transient_for was getting set on a Gimp offscreen window and that caused a
crash in raise_transient.
Some applications need to access gdk_quartz_window_get_nsview,
gdk_quartz_window_get_nswindow, and gdk_quartz_event_get_nsevent
so move these from the private gdkquartz-gtk-only.h to a new
header gdkquartz-cocoa-access.h. Don't include this header in
gdkquartz.h so that user code that doesn't need to access these
functins isn't required to compile with Objective C/C++.
Closes https://gitlab.gnome.org/GNOME/gtk/-/issues/1737
Closes: https://gitlab.gnome.org/GNOME/gtk/issues/1737
Don't export any functions taking or returning MacOS types in
gdkquartz.h, gdkprivate-quartz.h, or any header that either includes.
The GdkQuartz internal functions are moved to a new header
gdkinternal-quartz.h, the functions used by quartz-specific
Gtk files are moved to another new header gdkquartz-gtk-only.h, and
the key and event enums to a new header gdkkeys-quartz.h.
https://bugzilla.gnome.org/show_bug.cgi?id=784723 introduced support for
native file chooser dialogs on macOS, but due to the use of generics in
the patch, there will be compilation errors on pre-Xcode 7 platforms,
such as Mountain Lion and Mavericks.
I strongly recommend to revert this patch when the oldest supported
macOS release is bumped to Yosemite (10.10).
https://bugzilla.gnome.org/show_bug.cgi?id=785306
