Remove static destructors from Windows-specific files.

Blink coding style is to generally avoid these by having a static pointer to the
non-POD type, initializing it with an inline if, and letting it leak. However,
there are a few instances where that style is violated and these are causing
trouble by illegally touching Blink objects after WebKit::shutdown has been
called.

Easy to fix: three sites switched to standard style.

TBR=inferno@chromium.org
BUG=270531

Review URL: https://codereview.chromium.org/26355008

git-svn-id: svn://svn.chromium.org/blink/trunk@159693 bbb929c8-8fbe-4397-9dbb-9b2b20218538