Revert of Add CompleteRead to SequencedSocketData and convert all but 3 tests

Revert of Add CompleteRead to SequencedSocketData and convert all but 3 tests (patchset #2 id:20001 of https://codereview.chromium.org/1124533002/)

Reason for revert:
Suspected of having broken net_unittests on Win 7:
https://findit-for-me.appspot.com/build-failure?url=https://build.chromium.org/p/chromium.win/builders/Win%207%20Tests%20x64%20(1)/builds/1337
https://findit-for-me.appspot.com/build-failure?url=https://build.chromium.org/p/chromium.win/builders/Win7%20Tests%20(1)/builds/38402

Also unblocks revert of previous, dependent CL.

Original issue's description:
> Add CompleteRead to SequencedSocketData and convert all but 3 tests
> to use SequencedSocketData.  Reduces runtime to 7 seconds from 11 seconds on my linux workstation
>
> BUG=332112
>
> Committed: https://crrev.com/d7b1887392866667126162a4e7854a2736449970
> Cr-Commit-Position: refs/heads/master@{#328221}

TBR=rtenneti@chromium.org,rch@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=332112
Committed: https://crrev.com/cd6674c77dbeaa9c17bdf2dea1ca1c521649c8fa
Cr-Commit-Position: refs/heads/master@{#328252}

[Dan Beam, 2015-05-05 01:55:40]

Created Revert of Add CompleteRead to SequencedSocketData and convert all but 3
tests

[commit-bot: I haz the power, 2015-05-05 01:56:41]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1129473002/1

[commit-bot: I haz the power, 2015-05-05 01:58:06]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-05-05 01:59:09]

Patchset 1 (id:??) landed as
https://crrev.com/cd6674c77dbeaa9c17bdf2dea1ca1c521649c8fa
Cr-Commit-Position: refs/heads/master@{#328252}