[Loader] Add asserts about revalidation and redirects

[Loader] Add asserts about revalidation and redirects

After https://codereview.chromium.org/2011283002/ and
https://codereview.chromium.org/2017883002/, redirect chain must be empty
when revalidation starts or during revalidation is ongoing.
This CL adds asserts to verify that.

BUG=613971, 614989
Review-Url: https://codereview.chromium.org/2020253002
Cr-Commit-Position: refs/heads/master@{#397683}
(cherry picked from commit d0753f72046d160bc34584a47eb3f3a3c56daff1)

Committed: https://chromium.googlesource.com/chromium/src/+/762426dfb504e5b631ee0b48ffe9e3ba7f7ba6e3

[hiroshige, 2016-06-08 04:23:09]

Description was changed from

==========
[Loader] Add asserts about revalidation and redirects

After https://codereview.chromium.org/2011283002/ and
https://codereview.chromium.org/2017883002/, redirect chain must be empty
when revalidation starts or during revalidation is ongoing.
This CL adds asserts to verify that.

BUG=613971, 614989

Review-Url: https://codereview.chromium.org/2020253002
Cr-Commit-Position: refs/heads/master@{#397683}
(cherry picked from commit d0753f72046d160bc34584a47eb3f3a3c56daff1)
==========

to

==========
[Loader] Add asserts about revalidation and redirects

After https://codereview.chromium.org/2011283002/ and
https://codereview.chromium.org/2017883002/, redirect chain must be empty
when revalidation starts or during revalidation is ongoing.
This CL adds asserts to verify that.

BUG=613971, 614989

Review-Url: https://codereview.chromium.org/2020253002
Cr-Commit-Position: refs/heads/master@{#397683}
(cherry picked from commit d0753f72046d160bc34584a47eb3f3a3c56daff1)

Committed:
https://chromium.googlesource.com/chromium/src/+/762426dfb504e5b631ee0b48ffe9...
==========

[hiroshige, 2016-06-08 04:23:11]

Committed patchset #1 (id:1) manually as
762426dfb504e5b631ee0b48ffe9e3ba7f7ba6e3.