Continue with the FreeBSD port - this version builds and links, though...

app/app.gyp

Index: app/app.gyp
===================================================================
--- app/app.gyp	(revision 25977)
+++ app/app.gyp	(working copy)
@@ -16,7 +16,7 @@
       ['exclude', '/(gtk|win|x11)_[^/]*\\.cc$'],
     ],
     'conditions': [
-      ['OS=="linux"', {'sources/': [
+      ['OS=="linux" or OS=="freebsd"', {'sources/': [
         ['include', '/gtk/'],
         ['include', '_(gtk|linux|posix|skia|x)\\.cc$'],
         ['include', '/(gtk|x11)_[^/]*\\.cc$'],
@@ -125,7 +125,7 @@
         ],
       },
       'conditions': [
-        ['OS=="linux"', {
+        ['OS=="linux" or OS=="freebsd"', {
           'dependencies': [
             # font_gtk.cc uses fontconfig.
             # TODO(evanm): I think this is wrong; it should just use GTK.
@@ -167,7 +167,7 @@
             'os_exchange_data.cc',
           ],
         }],
-        ['OS!="linux"', {
+        ['OS!="linux" and OS!="freebsd"', {
           'sources!': [
             'gtk_dnd_util.cc',
             'gtk_dnd_util.h',
@@ -206,7 +206,7 @@
         '..',
       ],
       'conditions': [
-        ['OS=="linux"', {
+        ['OS=="linux" or OS=="freebsd"', {
           # TODO: Move these dependencies to platform-neutral once these
           # projects are generated by GYP.
           'dependencies': [