Store the locale format in a static cache to avoid re-computing it dozens of times on calendar views.

Issue #874322, Add back the date_field_all_day() function to avoid breaking other modules that are using it.

Issue #1236216, Start the process of moving the repeating date integration out of the Date module and into a separate, Date Repeat Field module.

Issue #874322, The All Day functionality has been moved into a separate module and hooks were added to make it easier for other modules to inject steps into date processing.

Issue #1217796, Make sure that All Day formatting works correctly even if the All Day label is empty.

Issue #1302374 by miro_dietiker, Account for an inconsistency in core handling of non-existant date formats.

Issue #1292898, Check for all day checkbox in the basic date element validation so empty time for newly added elements still passes validation.

Issue #1153766, Adapt metadata functions to the pattern in the current Entity code, add  to the getters.

Issue #1179716, Remove value_callback for date_repeat and date_combo forms, the default behavior works fine.

Issue #1257830, Beef up the logic when creating the date repeat tabs to work for more kinds of entities.

Issue #1216878, Re-introduce 'repeat' as a field setting rather than a widget type so people can't try to switch back and forth between repeating and non-repeating dates. Eliminate repeat widgets.

Issue #1249724 by KarenS, Gábor Hojtsy, David_Rothstein, Improve usability of date and time input configuration.

Issue #1251592 by David_Rothstein, Set reasonable default values if date formats have not been configured, and add tests for that.

Issue #1234140 by arlinsundbulte, Change terminology in user-facing text from 'From/To Date' to 'Start/End Date'.

Issue #1229362, Date Popup module needs date_is_date() function, which should not require Date module. Move that to Date API.