Skip useless processing for converted types

[stephan]

When the SourceTypeConverter creates type declarations it is configured by a bitset (flags) saying which elements are needed (METHOD, MEMBER_TYPE) etc.

Currently, we mark converted types with a boolean flag isConverted to skip some analysis on converted types. When debugging a runtime workbench many processes recored many compile errors due to missing elements. We should short-cut this by recording the full bitset in each converted type declaration. Then, e.g., the MethodMappingResolver can be completely skipped if METHOD is not in the bitset.

This will make debugging easier and additionally might improve performance of many of those non-builder calls into the compiler.