Fix issue in IJM where view becomes invalid.

Sometimes, by the the time we start the jank tracker, the view,
which was validated at CUJ begin by the configuration, becomes
invalid, which would cause an NPE later on. If the view is invalid
at frame tracker start, abort the CUJ.

Bug: b/320527356
Test: manual
Flag: EXEMPT bug fix
Change-Id: I8959263a9c344b773912b96d77108a2e56139db6