Remove multiple GC calls and replace GCController.collect calls with GCController.collectAll

BUG=307614,288072
NOTRY=true

Review URL: https://codereview.chromium.org/211933008

git-svn-id: svn://svn.chromium.org/blink/trunk@170018 bbb929c8-8fbe-4397-9dbb-9b2b20218538