GitLab

* Remove empty Linux & Win implementations of the class.
* Rename files and unit test to be Mac only.
* Rename namespace SpellCheckerPlatform -> SpellCheckerMac
* Surround usage in crossplatform files with #ifdef OS_MACOSX as a temporary measure (a future step will be to remove the calls entirely from these files).

BUG=69944
TEST=Spelling correction feature should continue to work as expected on Mac/Win/Linux .


Review URL: http://codereview.chromium.org/8890022

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@113974 0039d316-1c4b-4281-b951-d872f2087c98