Some editors use diagnostics from SourceKit to replace build issues. This causes issues if the diagnostics from SourceKit are formatted differently than the build issues. Make sure they are rendered the same way, removing most uses of `DiagnosticsEditorMode`.
To do so, always emit the `add stubs for conformance` note (which previously was only emitted in editor mode) and remove all `; add <something>` suffixes from notes that state which requirements are missing.
rdar://129283608
The test/Parse/enum.swift test was only enabled for Intel platforms because a
few of the contained test cases relied on floating point literal parsing and
were not portable as a result. Subset out the non-portable test cases into a
new test so that more general enum parsing tests can run on all platforms.
