[gnome-builder] libide: add missing headers

[Christian Hergert <chergert src gnome org>]

commit 0262f0e50f40a840e5db4f4682d6d4d86d2ae19e
Author: Christian Hergert <christian hergert me>
Date:   Sun Feb 21 20:48:58 2016 -0800

    libide: add missing headers

 libide/Makefile.am |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/libide/Makefile.am b/libide/Makefile.am
index 1fd140f..af028a8 100644
--- a/libide/Makefile.am
+++ b/libide/Makefile.am
@@ -144,6 +144,9 @@ libide_1_0_la_public_headers = \
        preferences/ide-preferences-flow-box.h \
        preferences/ide-preferences-font-button.h \
        preferences/ide-preferences-group.h \
+       preferences/ide-preferences-page.h \
+       preferences/ide-preferences-spin-button.h \
+       preferences/ide-preferences-switch.h \
        search/ide-omni-search-display.h \
        search/ide-omni-search-entry.h \
        search/ide-omni-search-group.h \