e_policy_visibility: modify code to consider the child's launch cancel while waiting uniconify of child
If the child window is to be hidden (by visibility) while the parent window is waiting for uniconify of child window,
then the uniconify_render timeout is occurred because the parent cannot get the e,action,launch,done signal of the child window.
So, we add e,action,launch,cancel signal event and use this to prevent the timeout of above case.
Change-Id: I1d1c2c5a200134c0eb7a668470172d95fddff2fb