Modified not to occur NPE when handle call of failed connection

Modified not to occur system crash by checking whether call which is matched with the call ID is null or not.

Bug: 186181672
Test: Occured when call of failed connection is null.

Signed-off-by: Junyeong Bak <junyeong.bak@samsung.com>
Change-Id: I50f797d9851ebb9c3df4377af59a687c759bc200
1 file changed