Revert of Presubmit: Warn about useless forward declarations

Revert of Presubmit: Warn about useless forward declarations (patchset #1 id:1 of https://codereview.chromium.org/2525263002/ )

Reason for revert:
Warning too aggressively + doesn't work with deleted files.

Original issue's description:
> Presubmit: Warn about useless forward declarations
>
> Checks that affected header files do not contain useless class
> or struct forward declaration.
>
> BUG=662195
> TEST=PRESUBMIT_test.py ForwardDeclarationTest
>
> Committed: https://crrev.com/1ae91afd6ab12165d8bd7981b9984fe7aec8d3d2
> Cr-Commit-Position: refs/heads/master@{#434329}

TBR=jochen@chromium.org,dpranke@google.com,phajdan.jr@chromium.org,asvitkine@chromium.org,jbriance@cisco.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=662195
Committed: https://crrev.com/10912d9e7cf31d99c99b19c94f1f076f68354c89
Cr-Commit-Position: refs/heads/master@{#434343}

[dcheng, 2016-11-24 16:31:53]

The CQ bit was checked by dcheng@chromium.org

[dcheng, 2016-11-24 16:31:54]

Created Revert of Presubmit: Warn about useless forward declarations

[dcheng, 2016-11-24 16:32:03]

The CQ bit was unchecked by dcheng@chromium.org

[dcheng, 2016-11-24 16:32:51]

The CQ bit was checked by dcheng@chromium.org

[commit-bot: I haz the power, 2016-11-24 16:33:20]

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, 2016-11-24 16:34:17]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1480005171389950, "parent_rev":
"1efb4776df34fdbddda1edb35538d62059301cbb", "commit_rev":
"26eac686cb80ee7dc5025b109b9ee6ca935f5c12"}

[commit-bot: I haz the power, 2016-11-24 16:34:42]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-11-24 16:38:31]

Description was changed from

==========
Revert of Presubmit: Warn about useless forward declarations (patchset #1 id:1
of https://codereview.chromium.org/2525263002/ )

Reason for revert:
Warning too aggressively + doesn't work with deleted files.

Original issue's description:
> Presubmit: Warn about useless forward declarations
> 
> Checks that affected header files do not contain useless class
> or struct forward declaration.
> 
> BUG=662195
> TEST=PRESUBMIT_test.py ForwardDeclarationTest
> 
> Committed: https://crrev.com/1ae91afd6ab12165d8bd7981b9984fe7aec8d3d2
> Cr-Commit-Position: refs/heads/master@{#434329}

TBR=jochen@chromium.org,dpranke@google.com,phajdan.jr@chromium.org,asvitkine@...
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=662195
==========

to

==========
Revert of Presubmit: Warn about useless forward declarations (patchset #1 id:1
of https://codereview.chromium.org/2525263002/ )

Reason for revert:
Warning too aggressively + doesn't work with deleted files.

Original issue's description:
> Presubmit: Warn about useless forward declarations
>
> Checks that affected header files do not contain useless class
> or struct forward declaration.
>
> BUG=662195
> TEST=PRESUBMIT_test.py ForwardDeclarationTest
>
> Committed: https://crrev.com/1ae91afd6ab12165d8bd7981b9984fe7aec8d3d2
> Cr-Commit-Position: refs/heads/master@{#434329}

TBR=jochen@chromium.org,dpranke@google.com,phajdan.jr@chromium.org,asvitkine@...
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=662195

Committed: https://crrev.com/10912d9e7cf31d99c99b19c94f1f076f68354c89
Cr-Commit-Position: refs/heads/master@{#434343}
==========

[commit-bot: I haz the power, 2016-11-24 16:38:32]

Patchset 1 (id:??) landed as
https://crrev.com/10912d9e7cf31d99c99b19c94f1f076f68354c89
Cr-Commit-Position: refs/heads/master@{#434343}