All Java classes extend java.lang.Object (directly or indirectly)
ifEmpty for collections
Constructors supported
printAndReturn() added
Adding submodule to the context
isEmpty() and flatten() added
Differentiate package fragments loaded from java packages and java (static) classes
Proper toString() added to lazy classes
Properly load Java classes as packages
Resolve functions in packages loaded from Java classes
All extra services delivered through contexts
Error class descriptor must not fail an attempt to create a type with arguments from it
Don't fail on star projections for error types
Support overrides in Java classes
Support loading Java fields as properties
isError() implemented for lazy java types
Propagation and alternative signatures for functions in Java
No need for applyNullability()
Take care of Java's constructor type parameters
Properly transforming type parameters in case of raw types, and mismatches between parameter and argument numbers

NOTE: JetType.getArguments() now implies that JetType.getConstructor() is computed. In most use cases this happens anyways due to the logic of the client code