OTS rejects gw432047.ttf because the font is broken. We should not use
it. Instead, use a variant of the Ahem-font which has a variation
selector for 'a'. When a variation selector U+E0100 follows 'a', the
glyph for 'a' should be the same glyph as 'p' (which is a 0.2em height
rectangle) on platforms which support IVS (Note that we don't support
IVS yet on some platforms).

I use a script[1] to create this font.

[1] https://gist.github.com/bashi/1048e2e84394723fdc65

BUG=461128

Review URL: https://codereview.chromium.org/954603003

git-svn-id: svn://svn.chromium.org/blink/trunk@190743 bbb929c8-8fbe-4397-9dbb-9b2b20218538