remove some pre vs2013 code
remove some pre vs2013 code

We only support building for windows with Visual Studio 2013 Update 4
now, so let's remove dead code that is only used for older Visual
Studio versions.

BUG=442035

Review URL: https://codereview.chromium.org/803763002

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@187108 bbb929c8-8fbe-4397-9dbb-9b2b20218538

primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs