Fix storage page slow loading issue

StorageAsyncLoader is the bottleneck. It needs to loop all installed
apps and count all apps size. Original design was waiting the
asyncLoader went back then hide the loading icon. Change the design
to hide the loading icon before asyncLoader is back.

Fixes: 138964123
Test: manual
Change-Id: I54c2efa7cf61d711145811619512d927adcee210