Preload non-bootclasspath Java lib ClassLoaders.

This is specifically for HIDL but is applicable to other libs.

Classes on the bootclasspath are implicitly used by apps. For this
reason, many classes should not go there. However, there are some
libraries which are used by many apps/processes which are still
nice to preload the ClassLoaders of.

Now, cacheNonBootclasspathSystemLibs in ApplciationLoaders keeps
a map of jar -> ClassLoader in zygote to be retrieved by child
processes.

Bug: 128529256
Bug: 127406460
Test: boot Pixel 2, verify libs are preloaded and used, try apps that
    use these libraries.
Test: grep for ClassLoaderContext errors, for instance:
 - ClassLoaderContext shared library size mismatch
 - ClassLoaderContext classpath element mismatch
Test: showmap on various processes which use the preloaded libs.

Change-Id: I351bf1679e9a928c10dca860b6cd6cb414c3bb8e