Problems reported:

parser/error_recovery/issue_46505_prime_3.crash:2:10: Expected '>' after this.
  Stream<List<Set<>>>
         ^^^^

parser/error_recovery/issue_46505_prime_3.crash:2:3: A method declaration needs an explicit list of parameters.
  Stream<List<Set<>>>
  ^^^^^^

parser/error_recovery/issue_46505_prime_3.crash:3:1: Expected a function body, but got '}'.
}
^

beginCompilationUnit(class)
  beginMetadataStar(class)
  endMetadataStar(0)
  beginClassOrNamedMixinApplicationPrelude(class)
    handleIdentifier(A, classOrMixinDeclaration)
    handleNoTypeVariables({)
    beginClassDeclaration(class, null, A)
      handleNoType(A)
      handleClassExtends(null, 1)
      handleClassNoWithClause()
      handleClassOrMixinImplements(null, 0)
      handleClassHeader(class, class, null)
      beginClassOrMixinBody(DeclarationKind.Class, {)
        beginMetadataStar(Stream)
        endMetadataStar(0)
        beginMember()
          beginMethod(null, null, null, null, null, Stream)
            handleNoType({)
            handleIdentifier(Stream, methodDeclaration)
            beginTypeVariables(<)
              beginMetadataStar(List)
              endMetadataStar(0)
              handleIdentifier(List, typeVariableDeclaration)
              beginTypeVariable(List)
                handleTypeVariablesDefined(List, 1)
                handleNoType(List)
              endTypeVariable(<, 0, null, null)
              handleRecoverableError(Message[ExpectedAfterButGot, Expected '>' after this., null, {string: >}], List, List)
            endTypeVariables(<, >)
            handleRecoverableError(MissingMethodParameters, Stream, Stream)
            beginFormalParameters((, MemberKind.NonStaticMethod)
            endFormalParameters(0, (, ), MemberKind.NonStaticMethod)
            handleNoInitializers()
            handleAsyncModifier(null, null)
            handleRecoverableError(Message[ExpectedFunctionBody, Expected a function body, but got '}'., null, {lexeme: }}], }, })
            handleInvalidFunctionBody({)
          endClassMethod(null, Stream, (, null, })
        endMember()
      endClassOrMixinBody(DeclarationKind.Class, 1, {, })
    endClassDeclaration(class, })
  endTopLevelDeclaration()
endCompilationUnit(1, )