[EFL, AppleWin] WTF.ConcatenateCharacterArrayAndEmptyString API test failed

[EFL, AppleWin] WTF.ConcatenateCharacterArrayAndEmptyString API test failed
<https://webkit.org/b/150153>

Unreviewed.

Just use simple arrays of LChar and UChar for this test instead of creating String
objects and then getting the characters8()/characters16() from them, since that
doesn't guarantee null-termination (the bug.)

* TestWebKitAPI/Tests/WTF/StringOperators.cpp:
(TestWebKitAPI::TEST):
(TestWebKitAPI::build): Deleted.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@191236 268f45cc-cd09-0410-ab3c-d52691b4dbfc