Bug 824927 - Accessibility check missing in b2g configure. r=ted

configure.in

@@ -5234,6 +5234,14 @@ if test "$ACCESSIBILITY"; then
     AC_DEFINE(ACCESSIBILITY)
 fi
 
+dnl ========================================================
+dnl Accessibility is required for the linuxgl widget
+dnl backend
+dnl ========================================================
+if test "${MOZ_WIDGET_TOOLKIT}" = "linuxgl" -a "$ACCESSIBILITY" != "1"; then
+    AC_MSG_ERROR(["Accessibility is required for the linuxgl widget backend"])
+fi
+
 dnl ========================================================
 dnl Disable printing
 dnl ========================================================