Call EnsureNSSHttpIOInit in the chimera build.

Call EnsureNSSHttpIOInit in the chimera build.

Otherwise we end up using the default NSS client and not
SystemURLRequestContext.

This is a minimal fix to be merged onto release branches.
A follow-up will revise this to be somewhat less error-prone.

BUG=539520
TEST=Open about:net-internals on Linux or Chrome OS
     Visit https://incomplete-chain.badssl.com/ in a new tab
     The Events tab of about:net-internals should show a fetch for http://crt.comodoca.com/COMODORSADomainValidationSecureServerCA.crt

Committed: https://crrev.com/a477a70ad63769c456ed87b78830e2ccbf75d583
Cr-Commit-Position: refs/heads/master@{#352536}

[davidben, 2015-10-05 19:07:10]

davidben@chromium.org changed reviewers:
+ rsleevi@chromium.org

[Ryan Sleevi, 2015-10-06 03:09:10]

lgtm

[davidben, 2015-10-06 03:09:32]

The CQ bit was checked by davidben@chromium.org

[commit-bot: I haz the power, 2015-10-06 03:10:06]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1384343002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1384343002/1

[commit-bot: I haz the power, 2015-10-06 04:39:10]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-06 04:39:59]

Patchset 1 (id:??) landed as
https://crrev.com/a477a70ad63769c456ed87b78830e2ccbf75d583
Cr-Commit-Position: refs/heads/master@{#352536}