Put getter functions on Script line-endings objects

Put getter functions on Script line-endings objects

This is a step towards having Blink no longer look directly at the
line endings array.  That prevented https://codereview.chromium.org/1137683003/
from landing.  Next step, after the roll, will be using these
functions in Blink.
R=jochen@chromium.org
BUG=

Committed: https://crrev.com/6ba8455e63712e9463685f63b22ffe64058adc9a
Cr-Commit-Position: refs/heads/master@{#29330}

[Erik Corry Chromium.org, 2015-06-26 10:47:12]

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

[commit-bot: I haz the power, 2015-06-26 10:47:22]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1213783002/1

[commit-bot: I haz the power, 2015-06-26 10:49:03]

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

[commit-bot: I haz the power, 2015-06-26 10:49:04]

Dry run: Exceeded global retry quota

[Erik Corry Chromium.org, 2015-06-26 11:04:32]

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

[commit-bot: I haz the power, 2015-06-26 11:04:37]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1213783002/20001

[commit-bot: I haz the power, 2015-06-26 11:08:00]

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

[commit-bot: I haz the power, 2015-06-26 11:08:01]

Dry run: Exceeded global retry quota

[Erik Corry Chromium.org, 2015-06-26 11:45:21]

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

[commit-bot: I haz the power, 2015-06-26 11:45:33]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1213783002/40001

[commit-bot: I haz the power, 2015-06-26 12:09:49]

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

[commit-bot: I haz the power, 2015-06-26 12:09:51]

Dry run: This issue passed the CQ dry run.

[Yang, 2015-06-26 14:20:04]

On 2015/06/26 12:09:51, commit-bot: I haz the power wrote:
> Dry run: This issue passed the CQ dry run.

lgtm

[Erik Corry Chromium.org, 2015-06-26 14:57:15]

The CQ bit was checked by erikcorry@chromium.org

[commit-bot: I haz the power, 2015-06-26 14:57:29]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1213783002/40001

[commit-bot: I haz the power, 2015-06-26 14:58:57]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-06-26 14:59:18]

Patchset 3 (id:??) landed as
https://crrev.com/6ba8455e63712e9463685f63b22ffe64058adc9a
Cr-Commit-Position: refs/heads/master@{#29330}