Don't try to move non visible contents in "Indent" command

Don't try to move non visible contents in "Indent" command

This patch makes "Indent" command not to try move non visible contents into
block quote.

The root cause of issue 343958 is "Indent" command calls
|moveParagraphWithClones()| with null |VisiblePosition| for start and end of
contents to move. This patch checks them before calling
|moveParagraphWithClones()|.

BUG=343958
TEST=LayoutTests/editing/execCommand/indent-no-visible-contents-crash.html

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=176735

[yosin_UTC9, 2014-06-23 03:40:05]

Could you review this patch?
Thanks in advance.

[Yuta Kitamura, 2014-06-23 06:34:06]

LGTM with nit

https://codereview.chromium.org/349143002/diff/20001/Source/core/editing/Inde...
File Source/core/editing/IndentOutdentCommand.cpp (right):

https://codereview.chromium.org/349143002/diff/20001/Source/core/editing/Inde...
Source/core/editing/IndentOutdentCommand.cpp:124: VisiblePosition endOfContents
= VisiblePosition(end);
nit: You can simplify this line with:

    VisiblePosition endOfContents(end);

[yosin_UTC9, 2014-06-23 06:52:19]

Thanks for reviewing!
Committing...

https://codereview.chromium.org/349143002/diff/20001/Source/core/editing/Inde...
File Source/core/editing/IndentOutdentCommand.cpp (right):

https://codereview.chromium.org/349143002/diff/20001/Source/core/editing/Inde...
Source/core/editing/IndentOutdentCommand.cpp:124: VisiblePosition endOfContents
= VisiblePosition(end);
On 2014/06/23 06:34:06, Yuta Kitamura wrote:
> nit: You can simplify this line with:
> 
>     VisiblePosition endOfContents(end);

Done.

[yosin_UTC9, 2014-06-23 08:03:59]

The CQ bit was checked by yosin@chromium.org

[commit-bot: I haz the power, 2014-06-23 08:04:28]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/yosin@chromium.org/349143002/40001

[commit-bot: I haz the power, 2014-06-23 09:06:46]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  win_blink_rel on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/win_blink_rel/builds/13086)

[commit-bot: I haz the power, 2014-06-23 09:46:01]

Change committed as 176735