Use EditingStrategy as template parameter to lastEditablePositionBeforePositionInRootAlgorithm templ

Use EditingStrategy as template parameter to lastEditablePositionBeforePositionInRootAlgorithm template function

This patch changes template parameter of
|lastEditablePositionBeforePositionInRootAlgorithm()| to |EditingStrategy| or
|EditingInComposedTreeStrategy| instead of |Position| or |PositionInComposedTre|
to match other implementation of editing template functions for improving
readability.

This patch is a preparation of making selection to handle granularity for web
component, http://crrev.com/1277863002

BUG=513568
TEST=n/a; No behavior changes

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=201213

[yosin_UTC9, 2015-08-26 07:15:46]

yosin@chromium.org changed reviewers:
+ hajimehoshi@chromium.org, yoichio@chromium.org

[yoichio, 2015-08-26 07:26:07]

lgtm

[yosin_UTC9, 2015-08-26 07:31:16]

The CQ bit was checked by yosin@chromium.org

[commit-bot: I haz the power, 2015-08-26 07:31:27]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1304353003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1304353003/1

[commit-bot: I haz the power, 2015-08-26 08:08:51]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=201213