shell: Use a meson option to determine that we're in a sandbox

meson.build

@@ -41,6 +41,7 @@ set_defines = [
   ['PACKAGE', meson.project_name()],
   ['PACKAGE_VERSION', meson.project_version()],
   ['VERSION', meson.project_version()],
+  ['PROFILE', get_option('profile')],
   # i18n
   ['GETTEXT_PACKAGE', control_center_gettext]
 ]

shell/cc-window.c

@@ -102,7 +102,7 @@ enum
 static gboolean
 in_flatpak_sandbox (void)
 {
-  return g_file_test ("/.flatpak-info", G_FILE_TEST_EXISTS);
+  return g_strcmp0 (PROFILE, "development") == 0;
 }
 
 static void