Revert of [test] Refactoring - Use subject/observer pattern for progress indicators.

Revert of [test] Refactoring - Use subject/observer pattern for progress indicators. (patchset #3 id:40001 of https://codereview.chromium.org/1171943002/)

Reason for revert:
might break stuff

Original issue's description:
> [test] Refactoring - Use subject/observer pattern for progress indicators.
>
> This should prevent bugs caused by missing super calls in
> overridden methods. The assumption is that methods of
> different indicators are independent.
>
> Committed: https://crrev.com/fbe973ff1722a6158a5b2babce9c1a32d26a1d3b
> Cr-Commit-Position: refs/heads/master@{#28866}

TBR=jkummerow@chromium.org,tandrii@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Committed: https://crrev.com/2a3962d9d2a7415378811f4d56522531332d5a3e
Cr-Commit-Position: refs/heads/master@{#28869}

[Michael Achenbach, 2015-06-09 15:31:45]

Created Revert of [test] Refactoring - Use subject/observer pattern for progress
indicators.

[commit-bot: I haz the power, 2015-06-09 15:32:14]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1163373005/1

[commit-bot: I haz the power, 2015-06-09 15:32:43]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-06-09 15:33:00]

Patchset 1 (id:??) landed as
https://crrev.com/2a3962d9d2a7415378811f4d56522531332d5a3e
Cr-Commit-Position: refs/heads/master@{#28869}

[tandrii(chromium), 2015-06-09 15:59:48]

lgtm

[Michael Achenbach, 2015-06-10 09:42:09]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/1176863002/ by machenbach@chromium.org.

The reason for reverting is: All build problems had other causes..