Revert "Remove old serializer" It caused a regression, crbug.com/510422

Revert "Remove old serializer" It caused a regression, crbug.com/510422

> Remove old serializer
>
> Remove old serializer (WebPageSerializerImpl) and its tests
> (WebPageSerializerTest and resources) and use PageSerializer for all
> serialization tasks in WebPageSerializer.
>
> --
>
> This review is part of set aiming to merge the two existing page
> serializers, WebPageSerializerImpl and PageSerializer into the latter
> one.
>
> In addition to this it moves all the old tests from
> WebPageNewSerializerTest and WebPageSerializerTest to the newer
> PageSerializerTest structure and splits out a test for MHTML into the
> MHTMLTest file.
>
> Note: This is a rebase and split of
> https://codereview.chromium.org/68613003 from Opera which was reverted
> due to failing tests. In addition to the rebase some smaller fixes was
> done to accommodate to changes in the code from when it was first
> landed.
>
> BUG=328354
> R=hajimehoshi@chromium.org
>
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=198151
>
> Review URL: https://codereview.chromium.org/1177733003

BUG=328354, 510422
TBR=hajimehoshi@chromium.org,gustav.tiger@sonymobile.com

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=200628

[tkent, 2015-08-17 02:10:47]

The CQ bit was checked by tkent@chromium.org

[commit-bot: I haz the power, 2015-08-17 02:10:51]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1295063002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1295063002/1

[commit-bot: I haz the power, 2015-08-17 02:49:48]

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

[commit-bot: I haz the power, 2015-08-17 02:49:49]

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

[tkent, 2015-08-17 03:06:47]

The CQ bit was checked by tkent@chromium.org

[commit-bot: I haz the power, 2015-08-17 03:06:57]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1295063002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1295063002/1

[commit-bot: I haz the power, 2015-08-17 03:10:59]

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

[commit-bot: I haz the power, 2015-08-17 03:11:00]

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

[tkent, 2015-08-17 03:30:21]

The CQ bit was checked by tkent@chromium.org

[commit-bot: I haz the power, 2015-08-17 03:30:26]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1295063002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1295063002/1

[commit-bot: I haz the power, 2015-08-17 04:12:10]

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

[commit-bot: I haz the power, 2015-08-17 04:12:11]

Try jobs failed on following builders:
  mac_chromium_rel_ng on tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)

[tkent, 2015-08-17 04:13:38]

The CQ bit was checked by tkent@chromium.org

[commit-bot: I haz the power, 2015-08-17 04:13:48]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1295063002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1295063002/1

[commit-bot: I haz the power, 2015-08-17 05:06:52]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=200628