[gimp] app: switch gimppaintcore-loops.c to C++

[N/A <ell src gnome org>]

commit e8a14deecfd356be995d24a613293847c8de2fda
Author: Ell <ell_se yahoo com>
Date:   Wed Apr 4 16:59:24 2018 -0400

    app: switch gimppaintcore-loops.c to C++
    
    Ditto.

 app/paint/Makefile.am                              |    2 +-
 ...imppaintcore-loops.c => gimppaintcore-loops.cc} |    5 +++++
 2 files changed, 6 insertions(+), 1 deletions(-)
---
diff --git a/app/paint/Makefile.am b/app/paint/Makefile.am
index 149edba..c056706 100644
--- a/app/paint/Makefile.am
+++ b/app/paint/Makefile.am
@@ -60,7 +60,7 @@ libapppaint_a_sources = \
        gimpmybrushsurface.h            \
        gimppaintcore.c                 \
        gimppaintcore.h                 \
-       gimppaintcore-loops.c           \
+       gimppaintcore-loops.cc          \
        gimppaintcore-loops.h           \
        gimppaintcore-stroke.c          \
        gimppaintcore-stroke.h          \
diff --git a/app/paint/gimppaintcore-loops.c b/app/paint/gimppaintcore-loops.cc
similarity index 99%
rename from app/paint/gimppaintcore-loops.c
rename to app/paint/gimppaintcore-loops.cc
index b6b60fc..8da1a6f 100644
--- a/app/paint/gimppaintcore-loops.c
+++ b/app/paint/gimppaintcore-loops.cc
@@ -20,6 +20,9 @@
 #include <gegl.h>
 #include <gdk-pixbuf/gdk-pixbuf.h>
 
+extern "C"
+{
+
 #include "paint-types.h"
 
 #include "operations/layer-modes/gimp-layer-modes.h"
@@ -436,3 +439,5 @@ mask_components_onto (GeglBuffer        *src_buffer,
         }
     }
 }
+
+} /* extern "C" */