Update errorprone to 2.0.5 and make it work with jdk7 and 8.

Update errorprone to 2.0.5 and make it work with jdk7 and 8.

The bots have jdk7 and dev machines have jdk8. One of the jars in
jdk is a dependency for errorprone. Older versions require don't work
with jdk8 and newer versions require jdk8. To get around this, I am
updating errorprone to the latest release and also just adding the
required jar, javac-1.9.0-dev-r2644-1.jar, to the errorprone/lib/
folder.

BUG=

Committed: https://crrev.com/bf3dc38d551c62f884eaaed5452fb3a94a4f25f9
Cr-Commit-Position: refs/heads/master@{#350881}

[mikecase (-- gone --), 2015-09-18 01:54:41]

mikecase@chromium.org changed reviewers:
+ jbudorick@chromium.org

[mikecase (-- gone --), 2015-09-22 21:26:14]

pinging this CL. If you're OK with adding in the javac
(https://github.com/google/error-prone-javac) that errorprone needs to build to
the errorprone/lib/ folder, I'd like to get this change in and then everything
should work (on dev machines and on the bots.)

[mikecase (-- gone --), 2015-09-23 00:04:20]

Updated the README.chromium in the errorprone git repo.
Updated the README.chromium in chromium to match, as well as DEPS.

[jbudorick, 2015-09-24 23:46:37]

lgtm

[mikecase (-- gone --), 2015-09-25 17:52:31]

The CQ bit was checked by mikecase@chromium.org

[commit-bot: I haz the power, 2015-09-25 17:53:13]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1354783003/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1354783003/20001

[mikecase (-- gone --), 2015-09-25 18:11:34]

The CQ bit was checked by mikecase@chromium.org

[mikecase (-- gone --), 2015-09-25 18:11:34]

The patchset sent to the CQ was uploaded after l-g-t-m from
jbudorick@chromium.org
Link to the patchset: https://codereview.chromium.org/1354783003/#ps40001
(title: "Rebase")

[commit-bot: I haz the power, 2015-09-25 18:12:35]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1354783003/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1354783003/40001

[commit-bot: I haz the power, 2015-09-25 19:19:53]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-09-25 19:22:39]

Patchset 3 (id:??) landed as
https://crrev.com/bf3dc38d551c62f884eaaed5452fb3a94a4f25f9
Cr-Commit-Position: refs/heads/master@{#350881}