ecore_x_2w: return value is wrong and add missing APIs

ecore_x_2w: return value is wrong and add missing APIs

for ecore_x_window_size_get API, it will return void, so the previous writing
 will return an INT.
And similar bug to ecore_x_default_screen_get and ecore_x_display_get

Before we are using Per-Build-Error to add the API changes.
To make x2w more helper for all APIs, they will be added.
In this patch, the missing ecore_x API was figured out, except ecore_x_icccm
 which will be added later soon.