Ant: Some changes to speed-up manual testing

    - Added 'precompile.disable' flag so as we can avoid precom-
      piling modules that saves about 25 secs., hence running
      certain tests is substantially faster, specially for
      individual tests.
    - Making 'test' depend on 'buildonly' instead of 'dist-dev'
      saving about 5 secs because the creation of distribution
      files is omitted: lib/gwt-dev.jar and staging/gwt-dev.jar
      are the same.
    - With this change and adding -Dprecompile.disable, presubmits
      in Jenkins are 35 secs faster.
    - Added a couple of missing flags to skip certain tests.

Change-Id: I120e96c788270eeabf1162b605d9497c08803117
5 files changed