Call _set_content_type in _create_input_context_done in im-ibus.so

TEST=password dialog in gnome-shell

Review URL: https://codereview.appspot.com/13255047
Avoid compiler error in ibus_engine_dbus_property_changed

Do not return a value in a function that returns void.

BUG=http://code.google.com/p/ibus/issues/detail?id=1650

Review URL: https://codereview.appspot.com/13334044
Patch from David King <dking@redhat.com>.
Check for gsettings-schema-convert for dconf support

BUG=http://code.google.com/p/ibus/issues/detail?id=1650

Review URL: https://codereview.appspot.com/13423043
Patch from David King <dking@redhat.com>.
Avoid g_type_init() deprecation errors for Vala souurces

Inject g_type_init() redefinition into C source generated from Vala.
This is needed as the current GLib dependency is 2.32, which includes
g_type_init(), is also used as the Vala target GLib version. Therefore,
the C sources generated from the Vala sources include g_type_init()
calls. As it was deprecated in GLib 2.35.0, this creates a warning
(which becomes an error and stops the build) when compiling against that
version or higher.