Make --watchfs a common command option.

Adding an options parameter to DiffAwareness#getCurrentView seems like the
simplest way to achieve that.

Alternatives considered:
1. Making the diff awareness modules stateful. However, I did not want to do so
as I've also been working on improving the module API to reduce state, or at
least to have a proper lifecycle management for any necessary state.

2. Making the watchFs flag a constructor parameter. However, that would also
invalidate any implementations that don't use the flag (of which we have
several).

3. Only passing in a single boolean flag instead of an options class provider;
however, this is a more principled, futureproof API, which allows other
modules / awareness implementations to use their own options.

RELNOTES: --watchfs is now a command option; the startup option of the same
    name is deprecated. I.e., use bazel build --watchfs, not blaze --watchfs
    build.

--
MOS_MIGRATED_REVID=136154395

0 files changed, 0 insertions, 0 deletions