Fix CTS android.app package testSetDismissMessage seldom fail issue

The test case will test dialog's dismiss method by invoking dialogDismiss(d). 
It start a Handler thread to process the dialog dismiss message. 
But it did not guarantee the Handler thread has the chance to be executed
 first.Sometimes, the checking callback will occur before the Handler thread's
 execution. It will has timing issue to fail.The fix suggestion is raise the
 priority for thread ht.

Change-Id: Iba87238feb9ba571d40bd0ca3bc8240ec8570f5d
Signed-off-by: Junjie Hu <junjie.hu@mediatek.com>
(cherry picked from commit 16c94b8da3c3bd890887931f7ee829c537137ea3)
1 file changed