linux: Round font sizes when going from points to pixels.

linux: Round font sizes when going from points to pixels.

Round point-based Pango font sizes to the nearest pixel.
Otherwise, we can end up with smaller UI fonts than GTK+ 2.0
apps in some cases.

This seems to be in line with what get_scaled_size() does in
Pango's pango/pangofc-fontmap.c, and gives me identically
sized text in Gimp 2.6.12 and Chrome when I set the
Gtk/FontName XSETTINGS property to "Arial 10".

Note that Chrome doesn't currently honor additional
fine-grained configuration performed via FontConfig, like
disabling antialiasing for fonts of a certain size. That'll
happen in a separate change.

BUG=375824
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=282204

[Daniel Erat, 2014-07-09 20:08:44]

i'd like to add a test for this, but i'm not sure how to isolate this code from
the system's DPI without jumping through a bunch of hoops. :-/

[msw, 2014-07-09 20:19:59]

Awesome!!! lgtm

[Daniel Erat, 2014-07-09 20:20:39]

The CQ bit was checked by derat@chromium.org

[commit-bot: I haz the power, 2014-07-09 20:22:24]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/derat@chromium.org/377413002/1

[commit-bot: I haz the power, 2014-07-10 01:03:47]

Change committed as 282204