Android: Remove enable_turbine flag (reland)

Now that r8 has been updated to remove unnecessary bridge methods and
turbine is turned back on for all targets, and robolectric has been
moved into android_deps, we no longer need this enable_turbine flag. Now
we can assume that all non-prebuilt java targets have a turbine header.

This is a reland of https://crrev.com/c/2219670.
Need to wait until https://crrev.com/c/2219111 lands first.

No code change except to remove now-obsolete third_party changes.

Tbr: agrieve@chromium.org
Bug: 1056299
Change-Id: I1c31234ff3d6e009428664e9327a6138e91c4e22
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2220246
Reviewed-by: Peter Wen <wnwen@chromium.org>
Commit-Queue: Peter Wen <wnwen@chromium.org>
Auto-Submit: Peter Wen <wnwen@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#772894}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: a45f9b6a13d104b6458a0be154d305826f1f0830
1 file changed