Remove OwnArrayPtr/PassOwnArrayPtr classes from WTF.

Since r157328 OwnPtr and OwnArrayPtr have very similar behavior so it looks sane to teach OwnPtr working with arrays and remove OwnArrayPtr.
This gives following benefits:
- significantly less code to maintain in WTF
- significantly less copy/paste code
- OwnPtr behavior is getting closer to base::scoped_ptr and std::unique_ptr (becoming more standard) which is good.

Review URL: https://codereview.chromium.org/26417003

git-svn-id: svn://svn.chromium.org/blink/trunk@159390 bbb929c8-8fbe-4397-9dbb-9b2b20218538