Fixed the resolution doesn't match LCD resolution when using Systeminfo DISPLAY attribute.

BUG=XWALK-1927
I printed <code>display_handle_mode</code> called times. The result is <code>display_handle_mode</code>will be called n times if wayland output supports n modes in which there must be a mode that is the current using mode. So we can check the flags value to determine if it is the current mode.