wayland_input: Fill in missing parts of the event structures

wayland_input: Fill in missing parts of the event structures

This patch ports the "Fill in missing parts of the event structures
(ev->root, ev->multi)." part of upstream commit:
======================================================================
commit 0a32212a79ada418dc12d7e76f93871032e0c4e3
Author: Chris Michael <cp.michael@samsung.com>
Date:   Tue Nov 19 10:34:27 2013 +0000

    Add support for storing mulitple touch points.
    Send events to properly focused surface.
    Fill in missing parts of the event structures (ev->root, ev->multi).

    Signed-off-by: Chris Michael <cp.michael@samsung.com>
======================================================================

Without this patch, ecore will report invalid mouse position, and
make some app get into run status. See PTREL-641 for details.

Change-Id: I7e739cd72dc732c46a16935645b524e28724b024
Signed-off-by: Alex Wu <zhiwen.wu@linux.intel.com>