Visual Studio Builds: Build gdkmm into gtkmm

See merge request !20

In the autotools builds, GDKMM is no longer built as a standalone DLL
but is instead part of the GTKMM DLL.  Make it the case in the Visual
Studio builds as well.  This makes things in line with what happens in
GTK master.

Also remove all traces of gdkmm.rc, since that is no longer used.

Add set/get_extra_menu() in Entry, Label, PasswordEntry, Text, TextView.
Add enum Gtk::PropagationLimit. And other changes.

and update gtk_extra_objects.defs and gtk_docs_override.xml.

Gtk::Popover and Gtk::Window implements the Gtk::Native interface.
Gtk::GestureMultiPress is renamed to GestureClick.
Many gtk classes have been made final, which means that gtkmm can't
override signal default handlers.

and update gtk_extra_objects.defs and gtk_vfuncs.defs.

* gtk/src/cssprovider.[ccg|hg]:
* gtk/src/linkbutton.hg: Signals have no default handlers.
GtkCssProviderClass and GtkLinkButtonClass have become private.
* gtk/src/menubutton.hg: Derive MenuButton from Widget instead of
ToggleButton. Add set/get/property_icon_name(), set/get/property_label().

and update gtk_extra_objects.defs.

833976a0 (comment 514865)

See also commit 1d768e0c

note to self: before merging, go for a walk, get some fresh air, wait a
few hours, check the diff again, and notice all the leftover mistakes...

builder: Remove old, ugly get_widget*() overloads

See merge request !17

Kjell suggested this here, so while I originally kept these and
implemented the nicer overloads in terms of them to retain backwards
compatibility and richer git diffs, let's instead see if we can simply
get rid of them, to encourage the far nicer API they offer.

!11 (comment 514243)

This is left over from when it was an output parameter.

3.94 has been and gone; the current preview version is 3.95, so
announce that this will arrive in the release of 3.96.

This confirms that the new get_object<T>() does not conflict with the
old get_object(), as well as making sure the latter works and gets the
same object again without any problem.

Close #43

Allow getting and casting to a subclass of Glib::Object in one line,
thus making it nicer to deal with non-widget objects in Builder files.

The non-template and template member functions act as distinct
overloads, meaning the new ones can be named get_object() also.

Add a Gtk::Adjustment to tests/builder, and check its refcounts are OK.
Also add a g_assert that (A) ensures that the test compiles, i.e. we got
the right type in the RefPtr and (B) checks we get the right :value out.
In case (B) seems frivolous, I did see it not working due to prop order!
Adjustment:value needs set after :lower|:upper as it is clamped by them.

While here, g_assert() the mm pointers/RefPtrs just to be fully paranoid

#43

This looks nicer and, of course, serves to test that they work properly.

#43

To avoid the cumbersome two-step process of declaring a pointer and then
passing it to get_widget[_derived]() for use as an output argument, add
overloads that return the pointer directly. Of course, now we have no
arg from which to deduce the type, so pass that as a template argument.

#43

and wasn't achieving anything by explicitly being here anyway - except
breaking the test at runtime!

See GTK commit bcfff5e46934cb7bb9bae0730d557a3ed0faf163:


> This is not an api we want to propagate anymore.
> If you need to, you can still emit the "clicked"
> action signal on a button using g_signal_emit_by_name.

* tools/extra_defs_gen/generate_defs_gtk.cc:
* gtk/src/gtk_extra_objects.defs:
* gtk/src/gtk_signals.defs: Update for Gtk::Text.

* gtk/src/snapshot.hg: Add push_opacity(), push_blur(), push_clip(),
perspective(), append_layout().

Should have been done in commit 4fb2ba9b

This merges libgdkmm-4.0 and libgtkmm-4.0 into one library.
It installs gdkmm's header files in $(includedir)/gtkmm-4.0/.
MSVC_NMake/ has not been fixed.

Gtk has made a similar modification.
See https://bugzilla.gnome.org/show_bug.cgi?id=773100

Fixes #48

* demos/gtk-demo/example_menus.cc: Use Gtk::Window::set_default_widget()
instead of the deleted Widget::set_can_default() and grab_default().
* gdk/src/surface.hg: Add property_frame_clock().
* gtk/src/builder.hg: gsize length -> gssize; length can be -1.
* gtk/src/menu.hg: Remove set_display().
* gtk/src/popover.hg: Add property_default_widget().
* gtk/src/widget.hg: Remove set/get/property_can_default(), grab_default(),
signal_display_changed(). Add activate_action(), activate_default().
* gtk/src/window.[ccg|hg]: Remove activate_focus(), activate_default().
Add property_default_widget(). Rename set_default() to set_default_widget(),
unset_default() to unset_default_widget().

* gdk/src/surface.[ccg|hg]: Remove set/get_group(), invalidate_rect(),
invalidate(), invalidate_region(), set_skip_taskbar_hint(),
set_skip_pager_hint(), set_urgency_hint().
* gtk/src/csslocation.[ccg|hg]: New files.
* gtk/src/cssprovider.hg: Replace CssProviderError by CssParserError and
CssParserWarning. Replace get_named() by load_named().
* gtk/src/csssection.[ccg|hg]: Remove enum CssSection::Type. Add create()
and to_string(). Replace get_[start|ned]_[line|position]() by
get_[start|end]_location().
* gtk/src/enums.hg: Add PickFlags.
* gtk/src/listbox.hg: Add set/get/property_show_separators().
* gtk/src/menubar.hg: Remove enum PackDirection. Remove
set/get/property_pack_direction(), set/get/property_child_pack_direction().
* gtk/src/widget.hg: Replace set/get/property_can_pick() by
set/get/property_can_target(). Remove pick_vfunc(), set/get_parent_surface().
Add PickFlags argument to pick().
* gtk/src/window.hg: Remove set/get/property_skip_taskbar_hint(),
set/get/property_skip_pager_hint(), set/get/property_urgency_hint().

and update gtk_vfuncs.defs, gtk_generate_[docs|enums|methods].sh.
Some gtk files have been moved from gtk+/gtk to gtk+/gtk/css.
The gtk_generate_*.sh scripts shall search for info in gtk/gtk/css.

and make other changes to update for the latest gtk4.
All child properties have been removed from gtk4.

and update gtk_signals.defs.patch, gtk_vfuncs.defs, generate_defs_gtk.cc.

and minor changes of the documentation of LayoutManager and LayoutChild.

* gdk/src/device.[ccg|hg]: Remove warp(), get_position(int& x, int& y),
get_surface_at_position(int& x, int& y).
Add get_surface_at_position(double& x, double& y).
* gdk/src/surface.hg: Remove set_role(),
get_device_position(..., int& x, int& y, ...).
* gtk/src/actionbar.hg: Remove child property.
* gtk/src/application.hg: Add signal_query_end().
* gtk/src/fixed.hg: Remove child properties. Add get_child_position().
* gtk/src/headerbar.hg:
* gtk/src/overlay.hg: Remove child properties.
* gtk/src/paned.hg: Remove child properties.
Add property_resize_child1/2(), property_shrink_child1/2(),
* gtk/src/popovermenu.hg: Remove child property. Add add_submenu().
* gtk/src/searchentry.hg: Add property_placeholder_text(),
property_actives_default().
* gtk/src/stylecontext.hg: Remove obsolete _IGNORE().
* gtk/src/toolbar.hg: Remove child properties.
* gtk/src/toolitem.hg: Add property_expand_item(), property_homogeneous().
* gtk/src/window.hg: Remove set/get/property_role(),
set/get/property_gravity(), move(), get_position().
* tools/m4/convert_gdk.m4: Remove conversions for GdkGrabOwnership.

and update gtk_docs_override.xml, gtk_vfuncs.defs and generate_defs_gtk.cc.