Assign shared libraries stable package ids

When a shared library package is loaded into an AssetManager, the
shared library will be assigned a unique package id. Subsequent
AssetManaagers that load a shared library of the same package name
as the original shared library will use previously assigned package
name. Shared libraries will have stable package ids throughout the
lifetime of application.

Bug: 140790224
Bug: 128496033
Test: libandroidfw_tests
Test: third-party app no longer crashes on open
Test: atest CtsHostsideWebViewTests
Change-Id: Idc0315be21ea00b74d1a918b7083ad655104c008