Freeze break: GNOME Shell: Calendar day names and "all day" badly ellipsized in French

[Owen Taylor <otaylor redhat com>]

Some fixed sizes cause the GNOME Shell calendar drop down to have
extensive ellipsization in French in other languages.

 https://bugzilla.gnome.org/show_bug.cgi?id=645693

While cosmetic, this is pretty prominent breakage for people testing
GNOME Shell in other languages (and spoils the work of the i18n team
to get everything in the calendar translated). The patch is only 
CSS changes, so worst possible outcome is we trade one layout bug for
another, but it looks right to me, and tests OK in English where
everything is short and fits.

- Owen