Remove StaleWhileRevalidateCacheControl feature.

Remove StaleWhileRevalidateCacheControl feature.

This feature will not be used in Blink in the immediate future, so
remove it.

There are no callers or users.

BUG=348877
TEST=compiled

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=201546

[Adam Rice, 2015-08-31 00:32:46]

ricea@chromium.org changed reviewers:
+ yhirano@chromium.org

[yhirano, 2015-08-31 05:13:44]

LGTM.

[Adam Rice, 2015-09-01 02:24:49]

ricea@chromium.org changed reviewers:
+ tkent@chromium.org

[Adam Rice, 2015-09-01 02:24:49]

+tkent for WebKit OWNERS.

[tkent, 2015-09-01 02:26:29]

lgtm

[Adam Rice, 2015-09-01 02:43:36]

The CQ bit was checked by ricea@chromium.org

[commit-bot: I haz the power, 2015-09-01 02:43:40]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1325613002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1325613002/1

[commit-bot: I haz the power, 2015-09-01 06:05:09]

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

[commit-bot: I haz the power, 2015-09-01 06:05:10]

Try jobs failed on following builders:
  linux_android_rel_ng on tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_android_r...)

[Adam Rice, 2015-09-01 09:57:04]

The CQ bit was checked by ricea@chromium.org

[commit-bot: I haz the power, 2015-09-01 09:57:12]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1325613002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1325613002/1

[commit-bot: I haz the power, 2015-09-01 10:02:17]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=201546