Improve generated "Not enough arguments." TypeError exceptions.

BUG=270033

Review URL: https://chromiumcodereview.appspot.com/24203002

git-svn-id: svn://svn.chromium.org/blink/trunk@157966 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Add page visibility observer support for Device Motion

Stop firing 'ondevicemotion' events when a tab goes invisible to optimize
battery life.

R=timvolodine@chromium.org
BUG=263411
TEST=fast/dom/DeviceMotion/page-visibility.html

Review URL: https://chromiumcodereview.appspot.com/23705010

git-svn-id: svn://svn.chromium.org/blink/trunk@157968 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove onBlocked() function from WebIDBCallbacks.

Looks like this functions is marked as deprecated and thus should be removed,
since there is no Chromium users we can remove this safely.

BUG=None
TEST=None, no functional change.
R=dgrogan@chromium.org,abarth@chromium.org

Review URL: https://chromiumcodereview.appspot.com/23475050

git-svn-id: svn://svn.chromium.org/blink/trunk@157969 bbb929c8-8fbe-4397-9dbb-9b2b20218538