Always setup the native bridge library

Always setup the native bridge library

... even if the string is empty. This will initialize the native bridge
library but mark it as unavailable.

- also, rename native_bridge_library_path to
native_bridge_library_filename to be closer to the actual meaning (it's
just the filename without any path).

Bug: 16404669

(cherry picked from commit I94628639691459d48d1fbf0841f36b68d51818e7)

Change-Id: I94628639691459d48d1fbf0841f36b68d51818e7