Add defensive code for signal missing when destroy handle

Add defensive code for signal missing when destroy handle

It seems that signal to quit task thread is missed when destroy handle,
so, call g_cond_wait_until instead of g_cond_wait after stop preview is called,
then, task thread can be quit although it does not receive signal.

[Version] 0.2.70
[Profile] Common
[Issue Type] Update
[Dependency module] N/A
[Test] [M(T) - Boot=(OK), sdb=(OK), Home=(OK), Touch=(OK), Version=tizen-3.0-mobile_20170206.3]

Change-Id: I9338a6bd779d9f19eae027f5a75f72f3b1498cba
Signed-off-by: Jeongmo Yang <jm80.yang@samsung.com>