Don't set animation pending when gaining fake control

There are 2 cases that an insets source control doesn't have a leash:
1. The server hasn't applied the transaction of the initialization of a
   leash yet.
2. The control is a fake control. It is dispatched when the insets
   source is shown transiently by the server and we don't want the
   client to change its layout.

We should only defer the insets animation for case 1. This CL uses
the insetsHint to tell if a control is fake or not.

Fix: 227083463
Test: atest --iterations 10 OpenAppNonResizeableTest
Change-Id: I45f75d8013f5723b782857101d070729cf082166