Removed unused forward decl from tab.h

Removed unused forward decl from tab.h

Review-Url: https://codereview.chromium.org/2650823009
Cr-Commit-Position: refs/heads/master@{#446186}
Committed: https://chromium.googlesource.com/chromium/src/+/ad475ed683320a15232dc23b6e933012c1a7c2fa

[pkl (ping after 24h if needed), 2017-01-26 00:48:17]

pkl@chromium.org changed reviewers:
+ rohitrao@chromium.org

[pkl (ping after 24h if needed), 2017-01-26 00:48:18]

This is forked off from https://codereview.chromium.org/2650563002/ to keep
unrelated changes out of the other CL.

Please CQ if LGTY. Thanks!

[rohitrao (ping after 24h), 2017-01-26 00:50:34]

The CQ bit was checked by rohitrao@chromium.org

[rohitrao (ping after 24h), 2017-01-26 00:50:34]

lgtm

[commit-bot: I haz the power, 2017-01-26 00:51:46]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-01-26 01:12:41]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1485391834048110, "parent_rev":
"f21a35d01fe3fbab752736526b6dbaa31172c310", "commit_rev":
"ad475ed683320a15232dc23b6e933012c1a7c2fa"}

[commit-bot: I haz the power, 2017-01-26 01:13:51]

Description was changed from

==========
Removed unused forward decl from tab.h
==========

to

==========
Removed unused forward decl from tab.h

Review-Url: https://codereview.chromium.org/2650823009
Cr-Commit-Position: refs/heads/master@{#446186}
Committed:
https://chromium.googlesource.com/chromium/src/+/ad475ed683320a15232dc23b6e93...
==========

[commit-bot: I haz the power, 2017-01-26 01:13:56]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/ad475ed683320a15232dc23b6e93...