Better rewrite rule flushing in `test_permalink_without_title()`.

This ensures that the test is not polluted by permalink structure changes in
earlier tests.

git-svn-id: https://develop.svn.wordpress.org/trunk@30529 602fd350-edb4-49c9-b593-d223f7449a82
Remove failing `test_network_limit()` XML-RPC test.

Test added as a patch on #21292.

Props MikeHansenMe.
See #30284.

git-svn-id: https://develop.svn.wordpress.org/trunk@30530 602fd350-edb4-49c9-b593-d223f7449a82
Color Schemes: fix the pointer UP arrow color, fixes #30460.

git-svn-id: https://develop.svn.wordpress.org/trunk@30531 602fd350-edb4-49c9-b593-d223f7449a82