Overloads for numeric types

Adds support for numeric types.
Requires some refactoring of our IDL type lists, since now need to
distinguish "numeric type".

Doing this, I realize that I need to refactor or it will get very redundant and complicated; will do in a followup.

Changes one interface: HTMLOptionsCollection

R=haraken
BUG=293561

Review URL: https://codereview.chromium.org/276253004

git-svn-id: svn://svn.chromium.org/blink/trunk@173875 bbb929c8-8fbe-4397-9dbb-9b2b20218538