--- a/configure.in
+++ b/configure.in
@@ -5015,27 +5015,31 @@ dnl enable once Signaling lands
     AC_DEFINE(MOZ_WEBRTC_SIGNALING)
 dnl enable once PeerConnection lands
     MOZ_PEERCONNECTION=1
     AC_DEFINE(MOZ_PEERCONNECTION)
     MOZ_SCTP=1
     MOZ_SRTP=1
     AC_DEFINE(MOZ_SCTP)
     AC_DEFINE(MOZ_SRTP)
+    if test -n "$MOZ_X11"; then
+      MOZ_WEBRTC_X11_LIBS="-lXext -lXdamage -lXfixes -lXcomposite"
+    fi
 else
     MOZ_SYNTH_PICO=
 fi
 
 AC_SUBST(MOZ_WEBRTC)
 AC_SUBST(MOZ_WEBRTC_LEAKING_TESTS)
 AC_SUBST(MOZ_WEBRTC_SIGNALING)
 AC_SUBST(MOZ_PEERCONNECTION)
 AC_SUBST(MOZ_WEBRTC_ASSERT_ALWAYS)
 AC_SUBST(MOZ_SCTP)
 AC_SUBST(MOZ_SRTP)
+AC_SUBST(MOZ_WEBRTC_X11_LIBS)
 
 dnl Use integers over floats for audio on B2G and Android, because audio
 dnl backends for those platforms don't support floats.
 if test "$OS_TARGET" = "Android"; then
     MOZ_SAMPLE_TYPE_S16=1
     AC_DEFINE(MOZ_SAMPLE_TYPE_S16)
     AC_SUBST(MOZ_SAMPLE_TYPE_S16)
 else
@@ -8127,17 +8131,17 @@ if test "$MOZ_TREE_CAIRO"; then
     AC_SUBST(QUARTZ_FONT_FEATURE)
     AC_SUBST(PNG_FUNCTIONS_FEATURE)
     AC_SUBST(QT_SURFACE_FEATURE)
     AC_SUBST(TEE_SURFACE_FEATURE)
 
     MOZ_CAIRO_OSLIBS='${CAIRO_FT_OSLIBS}'
 
     if test "$MOZ_X11"; then
-        MOZ_CAIRO_OSLIBS="$MOZ_CAIRO_OSLIBS $XLDFLAGS -lXext -lXdamage -lXfixes -lXcomposite -lXrender"
+        MOZ_CAIRO_OSLIBS="$MOZ_CAIRO_OSLIBS $XLDFLAGS -lXrender"
     fi
 
     CAIRO_FEATURES_H=gfx/cairo/cairo/src/cairo-features.h
 else
     PKG_CHECK_MODULES(CAIRO, cairo >= $CAIRO_VERSION)
     MOZ_CAIRO_CFLAGS="$CAIRO_CFLAGS"
     MOZ_CAIRO_LIBS="$CAIRO_LIBS"
     PKG_CHECK_MODULES(CAIRO_TEE, cairo-tee >= $CAIRO_VERSION)

--- a/media/webrtc/signaling/test/Makefile.in
+++ b/media/webrtc/signaling/test/Makefile.in
@@ -1,16 +1,17 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this file,
 # You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 LIBS = \
   $(XPCOM_LIBS) \
   $(NSPR_LIBS) \
   $(NSS_LIBS) \
+  $(MOZ_WEBRTC_X11_LIBS) \
   $(REALTIME_LIBS) \
   $(DEPTH)/xpcom/glue/$(LIB_PREFIX)xpcomglue_s.$(LIB_SUFFIX) \
   $(DEPTH)/media/mtransport/standalone/$(LIB_PREFIX)mtransport_s.$(LIB_SUFFIX) \
   $(DEPTH)/media/webrtc/signalingtest/signaling_ecc/$(LIB_PREFIX)ecc.$(LIB_SUFFIX) \
   $(DEPTH)/media/webrtc/signalingtest/signaling_sipcc/$(LIB_PREFIX)sipcc.$(LIB_SUFFIX) \
   $(DEPTH)/layout/media/webrtc/$(LIB_PREFIX)webrtc.$(LIB_SUFFIX) \
   $(DEPTH)/layout/media/$(LIB_PREFIX)gkmedias.$(LIB_SUFFIX) \
   $(DEPTH)/media/webrtc/trunk/testing/gtest_gtest/$(LIB_PREFIX)gtest.$(LIB_SUFFIX) \

--- a/toolkit/library/libxul.mk
+++ b/toolkit/library/libxul.mk
@@ -46,16 +46,17 @@ ifeq ($(MOZ_WIDGET_TOOLKIT),cocoa)
 OS_LIBS += -lcups
 endif
 
 EXTRA_DSO_LDOPTS += \
   $(LIBS_DIR) \
   $(MOZ_JS_LIBS) \
   $(NSS_LIBS) \
   $(MOZ_CAIRO_OSLIBS) \
+  $(MOZ_WEBRTC_X11_LIBS) \
   $(MOZ_APP_EXTRA_LIBS) \
   $(SQLITE_LIBS) \
   $(NULL)
 
 ifdef ENABLE_INTL_API
 ifdef JS_SHARED_LIBRARY
 EXTRA_DSO_LDOPTS += $(MOZ_ICU_LIBS)
 endif