Fix to library projects in Eclipse.

- Properly setup source attachment for library jar files.
- Force refresh the bin folder of libraries to make sure main projects
  pick up the changes.
- Force update the library container of parent projects when a library is
  recompile. This makes sure the parent projects are recompiled when a library
  code change.
- Fix how we check the libraries' res folders exist. This ensures we pick up
  all the res folders even if Eclipse isn't aware of them due to refresh issues.

Change-Id: Ie4b7ae770cfc782589a983ec654a11a1dfa4ef2d
3 files changed