Store override DB file path as ParcelFileDescriptor not FileInputStream

The file input stream is something we need carefully open and close.
We'd better avoid store it as a class parameter but a local temp param
 when it needs to use.

Test: GTS
Bug: 161327905
Change-Id: Iae4343275d41f80be8975c01c02b1a6c2927aa02
Merged-In: Iae4343275d41f80be8975c01c02b1a6c2927aa02
(cherry picked from commit 26b3e0e6)