get_the_date() should be calling get_post_time()

[Rarst]

Date/Time template tags follow a certain hierarchy with one exception:

• the_time() > get_the_time() > get_post_time() > mysql2date()
• the_modified_time() > get_the_modified_time() > get_post_modified_time() > mysql2date()
• the_date() > get_the_date() > mysql2date()
• the_modified_date() > get_the_modified_date() > get_post_modified_time() > mysql2date()

There is get_the_date() > get_post_time() level missing. Which means that low level get_post_time filter in it will only affect time branch, but not date branch. This is inconsistent and potentially unexpected.

Will work on a patch to adjust get_the_date() implementation.

[Rarst]

Changed get_the_date() to call get_post_time() for consistency.

[flixos90]

A few tests here could be useful, ensuring that the intended filters are fired for all these functions.

[Rarst]

Added test for hooks fired.

[SergeyBiryukov]

In 43591:

Date/Time: Make get_the_date() call get_post_time() for consistency with get_the_time().

Props Rarst.
Fixes #44490.