remove byte-accounting assert for crbug.com/536163

remove byte-accounting assert for crbug.com/536163

The change https://codereview.chromium.org/1274453002 is causing a breakage
on the Chrome OS builds. It is not clear how to easily revert because there is
a following on dependent change (https://codereview.chromium.org/1351983002) am
I am not too familiar with the revert process.

The simplest revert is to remove the DCHECK.

BUG=chromium:536163
LOG=n
NOTRY=true
R=machenbach@chromium.org, cmumford@chromium.org, hpayer@chromium.org

Committed: https://crrev.com/1fe1c74a376d1d34b42d0b6489475e62468ee223
Cr-Commit-Position: refs/heads/master@{#30959}

[Michael Achenbach, 2015-09-27 20:31:33]

machenbach@chromium.org changed reviewers:
+ machenbach@chromium.org

[Michael Achenbach, 2015-09-27 20:31:33]

lgtm - to quick fix the roll. If there are other problems left, I'd just revert
all CLs...

[Michael Achenbach, 2015-09-27 20:32:31]

I've added 'chromium:' prefix to bug number as otherwise, bugdroid won't make
the connection.

[Michael Achenbach, 2015-09-28 05:39:52]

I'll cq this in order to repair the roll asap.

[Michael Achenbach, 2015-09-28 05:40:07]

The CQ bit was checked by machenbach@chromium.org

[Michael Achenbach, 2015-09-28 05:40:13]

The CQ bit was unchecked by machenbach@chromium.org

[Michael Achenbach, 2015-09-28 05:40:37]

The CQ bit was checked by machenbach@chromium.org

[commit-bot: I haz the power, 2015-09-28 05:40:44]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1372693002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1372693002/1

[commit-bot: I haz the power, 2015-09-28 05:43:26]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-09-28 05:43:27]

Try jobs failed on following builders:
  v8_presubmit on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_presubmit/builds/6118)

[commit-bot: I haz the power, 2015-09-28 06:59:11]

Patchset 1 (id:??) landed as
https://crrev.com/1fe1c74a376d1d34b42d0b6489475e62468ee223
Cr-Commit-Position: refs/heads/master@{#30959}

[Michael Achenbach, 2015-09-28 06:59:12]

Committed patchset #1 (id:1) manually as
1fe1c74a376d1d34b42d0b6489475e62468ee223.