Make Document::caretRangeFromPoint() to work with :first-letter style

Make Document::caretRangeFromPoint() to work with :first-letter style

This patch makes Document::caretRangeFromPoint() to work with :first-letter style by changing HitTestResult class to know whether specified point is in a renderer for :first-letter or not. Because of text nodes having :first-letter style are associated to two renderer, one for first letter and another is rest of text, this patch changes nodeFromPoint() to rendererFromPoint() and makes Document::caretRangeFromPoint() to use it.

This patch is a part of fixing issue 174349. Another patch will make selection to work with :first-letter style.

BUG=n/a
TEST=LayoutTests/fast/dom/Document/CaretRangeFromPoint/caretRangeFromPoint-with-first-letter-style.html
R=ojan@chromium.org

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=159012

[yosin_UTC9, 2013-10-04 10:13:57]

Could you review this patch?
Thanks in advance.

P.S.
This patch is split from https://codereview.chromium.org/20681004/

Finally, I found Document.caretRangeFromPoint() for testing.

[ojan, 2013-10-04 17:36:25]

lgtm

https://codereview.chromium.org/25668008/diff/3001/LayoutTests/fast/dom/Docum...
File
LayoutTests/fast/dom/Document/CaretRangeFromPoint/caretRangeFromPoint-with-first-letter-style.html
(right):

https://codereview.chromium.org/25668008/diff/3001/LayoutTests/fast/dom/Docum...
LayoutTests/fast/dom/Document/CaretRangeFromPoint/caretRangeFromPoint-with-first-letter-style.html:32:
window.jsTestIsAsync = true;
This test doesn't need to be async if you're running it during onload.

Incidentally, you also probably don't need to run it onload either. You should
be able to run it synchronously.

[commit-bot: I haz the power, 2013-10-04 17:36:32]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/yosin@chromium.org/25668008/3001

[commit-bot: I haz the power, 2013-10-04 18:42:24]

Retried try job too often on linux_blink_rel for step(s) webkit_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=linux_blin...

[yosin_UTC9, 2013-10-07 07:41:41]

Committed patchset #2 manually as r159012 (presubmit successful).