Change DesktopRootWindowHostTizenX11 from DesktopRootWindowHostXwalk.

After this CL, only Tizen(tizenos=1) uses DesktopRootWindowHostTizenX11. Desktop
linux uses DesktopRootWindowHostX11.
We have changed DesktopRootWindowHostTizenX11 only for Tizen.
1. multi touch support
2. remove cursor logic
We will change DesktopRootWindowHostTizenX11 only for Tizen.
1. device scale factor support
2. application resume and pause support
3. etc..
So only Tizen should use this class.
Merge pull request #709 from luxtella/rootwindow

Change DesktopRootWindowHostTizenX11 from DesktopRootWindowHostXwalk.