Add expandedToParagraph() method to WebRange
https://bugs.webkit.org/show_bug.cgi?id=110618

Patch by Rouslan Solomakhin <rouslan@chromium.org> on 2013-02-25
Reviewed by Adam Barth.

Add a method expandedToParagraph() to WebRange to return a copy of the
range expanded to paragraph boundaries. This method is to be used to
query the spelling context around the misspelled word under cursor.

* public/WebRange.h:
(WebRange): Added expandedToParagraph() method declaration.
* src/WebRange.cpp:
(WebKit::WebRange::expandedToParagraph): Added method to copy range, expand the copied range to paragraph boundaries, and return the resulting range.
(WebKit): Added expandedToParagraph() method definition.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@144002 268f45cc-cd09-0410-ab3c-d52691b4dbfc