content: Rename DumpRenderTree references to test_runner.

content: Rename DumpRenderTree references to test_runner.

DumpRenderTree is gone, so now content_shell with --run-layout-test or
test_runner has taken its place.

BUG=None
R=avi@chromium.org,tkent@chromium.org

Committed: https://crrev.com/586674b4c3d26c37232ec13f07e4f2d1c7326be8
Cr-Commit-Position: refs/heads/master@{#353668}

[tfarina, 2015-10-12 20:35:07]

Kent, fyi.

[tkent, 2015-10-12 23:17:38]

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

[tkent, 2015-10-12 23:17:38]

lgtm

[Avi (use Gerrit), 2015-10-13 00:25:43]

lgtm

[tfarina, 2015-10-13 03:15:37]

The CQ bit was checked by tfarina@chromium.org

[commit-bot: I haz the power, 2015-10-13 03:16:07]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1401213002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1401213002/1

[commit-bot: I haz the power, 2015-10-13 03:20:51]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-13 03:21:37]

Patchset 1 (id:??) landed as
https://crrev.com/586674b4c3d26c37232ec13f07e4f2d1c7326be8
Cr-Commit-Position: refs/heads/master@{#353668}