Add a sequence number to SuggestedWords.

This allows testing for suggestion freshness in an asynchronous
suggestions world.

In-advance cherrypick of Ic76cd17568598d8534aec81e037f9e37f52eb6b4
because there's a merge conflict.

Bug: 11301597
Change-Id: I4aec765a975298fcac30a48dede73d2622224fe5
3 files changed
tree: 06701020cc589a1d03947ae0c972bf6d89912599
  1. dictionaries/
  2. java/
  3. native/
  4. tests/
  5. tools/
  6. Android.mk
  7. CleanSpec.mk