The 'run-pass' header cause a 'ui' test to execute the result. It is used
to test the lint output, at the same time ensure those lints won't cause
the source code to become compile-fail.
12 run-pass/run-pass-fulldeps tests gained the header and are moved to
ui/ui-fulldeps. After this move, no run-pass/run-pass-fulldeps tests should
rely on the compiler's JSON message. This allows us to stop passing
`--error-format json` in run-pass tests, thus fixing #36516.