Revert of Add a temporary check to investigate NavigationThrottle crash

Revert of Add a temporary check to investigate NavigationThrottle crash (patchset #1 id:1 of https://codereview.chromium.org/2971833002/ )

Reason for revert:
We collected the data we needed.

Original issue's description:
> Add a temporary check to investigate NavigationThrottle crash
> 
> This CL adds a temporay check to ensure we're not trying to add
> NavigationThrottles to a NavigationHandle twice. This is part of the
> investigation of several crashes around subresource filters
> NavigationThrottles.
> 
> BUG=736658
> CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation
> 
> Review-Url: https://codereview.chromium.org/2971833002
> Cr-Commit-Position: refs/heads/master@{#484363}
> Committed: https://chromium.googlesource.com/chromium/src/+/a9f628ff52bffcfcae37a669c8bae5da1c560364

TBR=csharrison@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=736658
Review-Url: https://codereview.chromium.org/2968193002
Cr-Commit-Position: refs/heads/master@{#484592}
Committed: https://chromium.googlesource.com/chromium/src/+/bee05730effbd6abf793a9d15f4379a1181a45cf

[clamy, 2017-07-06 14:58:21]

The CQ bit was checked by clamy@chromium.org

[clamy, 2017-07-06 14:58:21]

Created Revert of Add a temporary check to investigate NavigationThrottle crash

[commit-bot: I haz the power, 2017-07-06 14:58:37]

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, 2017-07-06 14:58:57]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1499353101204650, "parent_rev":
"d7b32792c24d871986beb9122802b2de86abf0f8", "commit_rev":
"bee05730effbd6abf793a9d15f4379a1181a45cf"}

[commit-bot: I haz the power, 2017-07-06 14:59:09]

Description was changed from

==========
Revert of Add a temporary check to investigate NavigationThrottle crash
(patchset #1 id:1 of https://codereview.chromium.org/2971833002/ )

Reason for revert:
We collected the data we needed.

Original issue's description:
> Add a temporary check to investigate NavigationThrottle crash
> 
> This CL adds a temporay check to ensure we're not trying to add
> NavigationThrottles to a NavigationHandle twice. This is part of the
> investigation of several crashes around subresource filters
> NavigationThrottles.
> 
> BUG=736658
> CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation
> 
> Review-Url: https://codereview.chromium.org/2971833002
> Cr-Commit-Position: refs/heads/master@{#484363}
> Committed:
https://chromium.googlesource.com/chromium/src/+/a9f628ff52bffcfcae37a669c8ba...

TBR=csharrison@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=736658
==========

to

==========
Revert of Add a temporary check to investigate NavigationThrottle crash
(patchset #1 id:1 of https://codereview.chromium.org/2971833002/ )

Reason for revert:
We collected the data we needed.

Original issue's description:
> Add a temporary check to investigate NavigationThrottle crash
> 
> This CL adds a temporay check to ensure we're not trying to add
> NavigationThrottles to a NavigationHandle twice. This is part of the
> investigation of several crashes around subresource filters
> NavigationThrottles.
> 
> BUG=736658
> CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation
> 
> Review-Url: https://codereview.chromium.org/2971833002
> Cr-Commit-Position: refs/heads/master@{#484363}
> Committed:
https://chromium.googlesource.com/chromium/src/+/a9f628ff52bffcfcae37a669c8ba...

TBR=csharrison@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=736658

Review-Url: https://codereview.chromium.org/2968193002
Cr-Commit-Position: refs/heads/master@{#484592}
Committed:
https://chromium.googlesource.com/chromium/src/+/bee05730effbd6abf793a9d15f43...
==========

[commit-bot: I haz the power, 2017-07-06 14:59:11]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/bee05730effbd6abf793a9d15f43...

[Charlie Harrison, 2017-07-06 15:00:24]

LGTM