Revert of Retry to add MockPresentationClient to use in layout tests.

Revert of Retry to add MockPresentationClient to use in layout tests. (patchset #4 id:60001 of https://codereview.chromium.org/907893002/)

Reason for revert:
While the LayoutTests only test the logic in the mocks and the plumbing, maintaining the mocks while working on the platform/public interface is a pain and requires landing patches simultaneously in Blink and Chromium repositories. There's no layout test using this anyway yet.
I'll add layout tests later when the Blink-Chromium interface is stable and maybe Blink is merged into Chromium.

Original issue's description:
> Retry to add MockPresentationClient to use in layout tests.
>
> Now there's a MockPresentationService that's owned by WebTestProxy and
> accepts private method calls from the tests.
>
> MockPresentationClient was moved to WebFrameTestProxy instance since
> we want one per each frame. Reset logic is added too to make tests more
> independent.
>
> BUG=412331
>
> Committed: https://crrev.com/57b3af2412a81a4c0abf54e0146c0f7bf5530249
> Cr-Commit-Position: refs/heads/master@{#316199}

TBR=mkwst@chromium.org,peter@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=412331
Committed: https://crrev.com/49001892c02a5287233acc68edaaf2e0dc981163
Cr-Commit-Position: refs/heads/master@{#318230}

[whywhat, 2015-02-26 14:18:06]

Created Revert of Retry to add MockPresentationClient to use in layout tests.

[commit-bot: I haz the power, 2015-02-26 14:18:28]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/963493002/1

[commit-bot: I haz the power, 2015-02-26 14:19:42]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-02-26 14:20:28]

Patchset 1 (id:??) landed as
https://crrev.com/49001892c02a5287233acc68edaaf2e0dc981163
Cr-Commit-Position: refs/heads/master@{#318230}