Remove remaining accessibility-related localized string functions.

We use Locale::queryString instead. Remove the following functinos:
 - AXAMPMFieldText();
 - AXDayOfMonthFieldText();
 - AXDateTimeFieldEmptyValueText();
 - AXHourFieldText();
 - AXMillisecondFieldText();
 - AXMinuteFieldText();
 - AXMonthFieldText();
 - AXSecondFieldText();
 - AXWeekOfYearFieldText();
 - AXYearFieldText();

BUG=298020
TEST=none; no behavior changes.

Review URL: https://codereview.chromium.org/26686009

git-svn-id: svn://svn.chromium.org/blink/trunk@159398 bbb929c8-8fbe-4397-9dbb-9b2b20218538