Use shared namespace for bundled app classloader

Allow bundled apps to reference platform native libraries
located in subdirectories of the default library path
(/system/lib/hw/* for example).

In addition to this bundled apps need to share native
libraries with default namespace. Added parameter to
ApplicationLoaders.createClassLoader() to do just that.

Bug: 26165097
Bug: 26164393
(cherry picked from commit 75b10ecc)

Change-Id: I836e5fed4713f2a605a5de673c40970ef6d988dd