Update Gamepad.axes / GamepadButton.value to match the latest specification

Update Gamepad.axes / GamepadButton.value to match the latest specification:
https://dvcs.w3.org/hg/gamepad/raw-file/default/gamepad.html#widl-Gamepad-axes
https://dvcs.w3.org/hg/gamepad/raw-file/default/gamepad.html#widl-GamepadButton-value

Those attributes should be of type double as per the specification but Blink
was still using float type as in older version of the specification. This can
lead to precision problem on JavaScript side.

This CL introduces temporary ENABLE_NEW_GAMEPAD_API #ifdefs to help with the
transition. Those will be removed once the Chromium side has been updated.

R=eseidel@chromium.org, bajones@chromium.org
BUG=344556
TEST=gamepad/gamepad-events-basic.html

Review URL: https://codereview.chromium.org/280393004

git-svn-id: svn://svn.chromium.org/blink/trunk@174428 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Let updateLayout do style recalc instead of styleResolverChanged.

In updateLayoutIgnorePendingStylesheets, updateLayout will make sure
updateRenderTreeIfNeeded is called. Hence, we can use deferred style recalc
for styleResolverChanged.

R=ojan@chromium.org
BUG=374162

Review URL: https://codereview.chromium.org/287053003

git-svn-id: svn://svn.chromium.org/blink/trunk@174429 bbb929c8-8fbe-4397-9dbb-9b2b20218538