[gtk+] Install gtkeventcontrollermotion.h

[Matthias Clasen <matthiasc src gnome org>]

commit 20bdb347cd6e1ed7a969506e3c2e0ef6c6958a5f
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Dec 12 10:38:11 2017 -0500

    Install gtkeventcontrollermotion.h
    
    Public headers need to be listed in gtk/meson.build.
    This was overlooked when I added the controller.

 gtk/meson.build |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/gtk/meson.build b/gtk/meson.build
index abaa4bc..be8cc45 100644
--- a/gtk/meson.build
+++ b/gtk/meson.build
@@ -437,6 +437,7 @@ gtk_public_headers = files([
   'gtkenums.h',
   'gtkeventcontroller.h',
   'gtkeventcontrollerscroll.h',
+  'gtkeventcontrollermotion.h',
   'gtkexpander.h',
   'gtkfilechooser.h',
   'gtkfilechooserbutton.h',