[NFC][clang] Refactor getCompilationPhases()+Types.def step 3.


[NFC][clang] Refactor getCompilationPhases()+Types.def step 3.

Dropping the 'u' entry and the entire Flags table from Types.def.
Now it'll be a bit easier to tablegenify this.

Differential Revision: https://reviews.llvm.org/D65308


Event Timeline

This doesn't seem to be NFC, it broke clangd tests.

Previously e.g. TY_ObjCXXHeader had the u flag and could be user-specified. After this change it can't.

One example buildbot: http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-ubuntu-fast/builds/52222/steps/test/logs/stdio

Reverted as rL367353, as I'm guessing the change in behavior was unintentional.