[ozone/wayland] Implement basic keyboard handling support

ui/ozone/platform/wayland/wayland_connection.cc

Index: ui/ozone/platform/wayland/wayland_connection.cc
diff --git a/ui/ozone/platform/wayland/wayland_connection.cc b/ui/ozone/platform/wayland/wayland_connection.cc
index 520b21f9f08a62f6b17332484c7e0d6a58a115db..6db7a8f67910b2cb4c3565208a6684452b63181f 100644
--- a/ui/ozone/platform/wayland/wayland_connection.cc
+++ b/ui/ozone/platform/wayland/wayland_connection.cc
@@ -227,6 +227,20 @@ void WaylandConnection::Capabilities(void* data,
   } else if (connection->pointer_) {
     connection->pointer_.reset();
   }
+  if (capabilities & WL_SEAT_CAPABILITY_KEYBOARD) {
+    if (!connection->keyboard_) {
+      wl_keyboard* keyboard = wl_seat_get_keyboard(connection->seat_.get());
+      if (!keyboard) {
+        LOG(ERROR) << "Failed to get wl_keyboard from seat";
+        return;
+      }
+      connection->keyboard_ = base::MakeUnique<WaylandKeyboard>(
+          keyboard, base::Bind(&WaylandConnection::DispatchUiEvent,
+                               base::Unretained(connection)));
+    }
+  } else if (connection->keyboard_) {
+    connection->keyboard_.reset();
+  }
   connection->ScheduleFlush();
 }