[gimp/gimp-2-10] libgimpwidgets: install gimpbusybox.h as public header

[Michael Natterer <mitch src gnome org>]

commit def91dfc59ad809317b943c51cdd65fc34d7f77b
Author: Michael Natterer <mitch gimp org>
Date:   Fri Jun 8 18:58:04 2018 +0200

    libgimpwidgets: install gimpbusybox.h as public header
    
    (cherry picked from commit b75cbcb417687eb3e245096d93af744c095db305)

 libgimpwidgets/Makefile.am | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/libgimpwidgets/Makefile.am b/libgimpwidgets/Makefile.am
index f16b4a56d0..50ec2ab548 100644
--- a/libgimpwidgets/Makefile.am
+++ b/libgimpwidgets/Makefile.am
@@ -215,6 +215,7 @@ libgimpwidgets_@GIMP_API_VERSION@_la_SOURCES = \
 
 libgimpwidgetsinclude_HEADERS = \
        gimpbrowser.h                   \
+       gimpbusybox.h                   \
        gimpbutton.h                    \
        gimpcairo-utils.h               \
        gimpcellrenderercolor.h         \