Increment zaura_shell version to 7 in client_base

This is needed to add support for zaura_surface_set_client_surface_id

Bug: 1011977
Test: NONE
Change-Id: I460e0d5a2a5f9f63f94035bfc0665691492ec21e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2090605Reviewed-by: Daniele Castagna <dcastagna@chromium.org>
Commit-Queue: Shawn Gallea <sagallea@google.com>
Cr-Commit-Position: refs/heads/master@{#747812}

components/exo/wayland/clients/client_base.cc

@@ -140,7 +140,7 @@ void RegistryHandler(void* data,
         wl_registry_bind(registry, id, &wp_presentation_interface, 1)));
   } else if (strcmp(interface, "zaura_shell") == 0) {
     globals->aura_shell.reset(static_cast<zaura_shell*>(
-        wl_registry_bind(registry, id, &zaura_shell_interface, 5)));
+        wl_registry_bind(registry, id, &zaura_shell_interface, 7)));
   } 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, 2)));