Prior to this commit code completion for .kts files was supported only
partially. Script has an implicit receiver - base class representing a
script itself, the point where its basic API resides. The knowledge of
this receiver was missing.
There are at least two context where this knowledge is crucial:
1. Code highlighting (worked fine)
2. Code completion (failed)
`FirScriptConfiguratorExtension` is responsible for filling
`FirScriptBuilder` with base script class (in addition to other
properties). See usages of [1] in its implementation.
The thing is that resolution during the completion works a bit
different. Instead of converting the entire `KtFile` it's interested
in `KtScript` only. See usages of [2].
`RawFirBuilder.Visitor.visitScript` is where implicit receivers were
missing.
Code completion and inspections applied to `.kts` files already have
`FirScript` and don't require its full reconstruction with expensive
`FirScriptConfiguratorExtension`. `RawFirBuilder.Visitor` was modified
to support sometimes already existing `FirElement`.
----------------------------------------------------------------
[1]: ScriptCompilationConfiguration.baseClass
[2]: RawFirBuilder.Visitor.convertScript
Andrei Klunnyi
6535278bd3