exo: Fix linux_dmabuf_v1 version in wl clients

linux_dmabuf_v1 has been updated, clients have been updated to
use "create_immed" that is available starting from v2, but we forgot
to bump up the version we pass to wl_registry_bind.

This patch updates the wayland test client code.

Bug: None
Test: wayland_rects_client --use-drm=rockchip on kevin now works.
Change-Id: I83b16f48e797a275208df7f3d7cccfed8f0a5e40
Reviewed-on: https://chromium-review.googlesource.com/956563Reviewed-by: David Reveman <reveman@chromium.org>
Commit-Queue: David Reveman <reveman@chromium.org>
Commit-Queue: Daniele Castagna <dcastagna@chromium.org>
Cr-Commit-Position: refs/heads/master@{#541922}

components/exo/wayland/clients/client_base.cc

@@ -108,7 +108,7 @@ void RegistryHandler(void* data,
         wl_registry_bind(registry, id, &zaura_shell_interface, 1)));
   } else if (strcmp(interface, "zwp_linux_dmabuf_v1") == 0) {
     globals->linux_dmabuf.reset(static_cast<zwp_linux_dmabuf_v1*>(
-        wl_registry_bind(registry, id, &zwp_linux_dmabuf_v1_interface, 1)));
+        wl_registry_bind(registry, id, &zwp_linux_dmabuf_v1_interface, 2)));
   } else if (strcmp(interface, "wl_subcompositor") == 0) {
     globals->subcompositor.reset(static_cast<wl_subcompositor*>(
         wl_registry_bind(registry, id, &wl_subcompositor_interface, 1)));