De-flakify http/tests/xmlhttprequest/origin-whitelisting-https.html

This started flakily failing with http://src.chromium.org/viewvc/blink/?revision=158065&view=revision.
The memory cache is provided results some but not all of the time, which is
changing the text output. This patch makes sure the urls are sufficiently
different that cache hits aren't an issue.

BUG=295538

Review URL: https://chromiumcodereview.appspot.com/24088013

git-svn-id: svn://svn.chromium.org/blink/trunk@158140 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove DecayArray & HasTrivialConstructor / Destructor

All this code was never used everywhere. DecayArray was an effort
to merge OwnPtr and OwnArrayPtr (https://webkit.org/b/75737) but
it never took off. This change didn't remove the Remove* functions
used only by DecayArray as they could be useful (and we would
remove most of the TypeTraits if we removed the unused functions).

Review URL: https://chromiumcodereview.appspot.com/24302002

git-svn-id: svn://svn.chromium.org/blink/trunk@158141 bbb929c8-8fbe-4397-9dbb-9b2b20218538