Fix missing EGL extension function exports.

BUG=angle:490

Change-Id: Ie4e7b0075f60676aa5f9fb51a0d6fb8f84b9ed90
Reviewed-on: https://chromium-review.googlesource.com/207140
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Shannon Woods <shannonwoods@chromium.org>
Tested-by: Geoff Lang <geofflang@chromium.org>
diff --git a/src/libEGL/libEGL.def b/src/libEGL/libEGL.def
index 48c1897..d7949d0 100644
--- a/src/libEGL/libEGL.def
+++ b/src/libEGL/libEGL.def
@@ -37,3 +37,5 @@
 
     ; Extensions
     eglGetPlatformDisplayEXT         @35
+    eglQuerySurfacePointerANGLE      @36
+    eglPostSubBufferNV               @37