Fix an issue that webkit-transform might impact fullscreen video

Fullscreen video should ignore all css transforms.

BUG=356282

Review URL: https://codereview.chromium.org/221333002

git-svn-id: svn://svn.chromium.org/blink/trunk@170810 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove V8PerIsolateData::current()

V8PerIsolateData::current() is not good because it calls v8::Isolate::GetCurrent(). This CL passes Isolate* around and remove V8PerIsolateData::current().

BUG=357144
NOTRY=true

Review URL: https://codereview.chromium.org/222003004

git-svn-id: svn://svn.chromium.org/blink/trunk@170811 bbb929c8-8fbe-4397-9dbb-9b2b20218538