Update includes:
- Changing syntax of `OI/`NI` tags from `<!NI;TAG!>` to `<!TAG{NI}!>`
- Fix some incorrect directives
- Change order of diagnostics in some places
- Remove ignored diagnostics from FIR test data (previously `DIAGNOSTICS` didn't work)
- Update FIR dumps in some places and add `FIR_IDENTICAL` if needed
- Replace all JAVAC_SKIP with SKIP_JAVAC directive
In particular, this commit includes:
* Attempt to abstract access to FirSourceElement via FirModifier
* Add more visit functions to DeclarationCheckersDiagnosticComponent
* Add messages+factories for 4 modifier-related errors and warnings
* Introduce FirModifierChecker
Disable annotation rendering in default type and descriptor renderers.
Preserve annotations in Android and Serialization plugins.
Update error texts in ide tests.
Nullability annotations in Java descriptors are rendered with context-dependent renderer.
#KT-20258 Fixed
Jinseong Jeon