SegmentedString::prepend should know if the prepended string is new or previously consumed

SegmentedString::prepend should know if the prepended string is new or previously consumed

This CL fixes the FIXME in SegmentedString::prepend partially.

This CL also fixes the test failures in upcoming CL: https://codereview.chromium.org/2121703002/
Before this CL, we messed up the m_numberOfCharactersConsumedPriorToCurrentString
counter when BackgroundHTMLInputStream is rewound for document.write inputs.

BUG=619141
Committed: https://crrev.com/0a5bb3d7a08957ac247f5d7c458b7a225d54d56c
Cr-Commit-Position: refs/heads/master@{#404116}

[kouhei (in TOK), 2016-07-07 05:56:36]

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

[kouhei (in TOK), 2016-07-07 05:56:36]

tkent-san: Would you take a look?

[kouhei (in TOK), 2016-07-07 05:56:50]

The CQ bit was checked by kouhei@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-07-07 05:57:10]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[tkent, 2016-07-07 06:04:10]

lgtm

[commit-bot: I haz the power, 2016-07-07 07:16:17]

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

[commit-bot: I haz the power, 2016-07-07 07:16:17]

Dry run: This issue passed the CQ dry run.

[kouhei (in TOK), 2016-07-07 09:43:20]

The CQ bit was checked by kouhei@chromium.org

[commit-bot: I haz the power, 2016-07-07 09:43:35]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-07-07 09:47:43]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-07-07 09:49:09]

Description was changed from

==========
SegmentedString::prepend should know if the prepended string is new or
previously consumed

This CL fixes the FIXME in SegmentedString::prepend partially.

This CL also fixes the test failures in upcoming CL:
https://codereview.chromium.org/2121703002/
Before this CL, we messed up the
m_numberOfCharactersConsumedPriorToCurrentString
counter when BackgroundHTMLInputStream is rewound for document.write inputs.

BUG=619141
==========

to

==========
SegmentedString::prepend should know if the prepended string is new or
previously consumed

This CL fixes the FIXME in SegmentedString::prepend partially.

This CL also fixes the test failures in upcoming CL:
https://codereview.chromium.org/2121703002/
Before this CL, we messed up the
m_numberOfCharactersConsumedPriorToCurrentString
counter when BackgroundHTMLInputStream is rewound for document.write inputs.

BUG=619141

Committed: https://crrev.com/0a5bb3d7a08957ac247f5d7c458b7a225d54d56c
Cr-Commit-Position: refs/heads/master@{#404116}
==========

[commit-bot: I haz the power, 2016-07-07 09:49:10]

Patchset 1 (id:??) landed as
https://crrev.com/0a5bb3d7a08957ac247f5d7c458b7a225d54d56c
Cr-Commit-Position: refs/heads/master@{#404116}