+ Ignore type bound of "? extends Object"
+ Resolve new "unnecessary @SuppressWarnings" with new test as a witness
+ Preserve null info from erased bound '? extends @nonnull Object'
+ normalize eea signature to fold +Ljava/lang/Object; to *
    + encode variants with null annotations as *1 or *0 resp.
+ Test adjustments

Fixes https://github.com/eclipse-jdt/eclipse.jdt.core/issues/5028