Problems reported:

parser/error_recovery/constructor_recovery_return_type:2:3: Constructors can't have a return type.
  void Foo() {
  ^^^^

parser/error_recovery/constructor_recovery_return_type:5:3: Constructors can't have a return type.
  void Foo() : initializer = true {
  ^^^^

parser/error_recovery/constructor_recovery_return_type:8:3: Constructors can't have a return type.
  void Foo.x() {
  ^^^^

parser/error_recovery/constructor_recovery_return_type:11:3: Constructors can't have a return type.
  void Foo.x() : initializer = true {
  ^^^^

beginCompilationUnit(class)
  beginMetadataStar(class)
  endMetadataStar(0)
  beginClassOrNamedMixinApplicationPrelude(class)
    handleIdentifier(Foo, classOrMixinDeclaration)
    handleNoTypeVariables({)
    beginClassDeclaration(class, null, Foo)
      handleNoType(Foo)
      handleClassExtends(null, 1)
      handleClassNoWithClause()
      handleClassOrMixinImplements(null, 0)
      handleClassHeader(class, class, null)
      beginClassOrMixinBody(DeclarationKind.Class, {)
        beginMetadataStar(void)
        endMetadataStar(0)
        beginMember()
          beginMethod(null, null, null, null, null, Foo)
            handleVoidKeyword(void)
            handleIdentifier(Foo, methodDeclaration)
            handleNoTypeVariables(()
            beginFormalParameters((, MemberKind.NonStaticMethod)
            endFormalParameters(0, (, ), MemberKind.NonStaticMethod)
            handleNoInitializers()
            handleAsyncModifier(null, null)
            beginBlockFunctionBody({)
            endBlockFunctionBody(0, {, })
            handleRecoverableError(ConstructorWithReturnType, void, void)
          endClassConstructor(null, void, (, null, })
        endMember()
        beginMetadataStar(void)
        endMetadataStar(0)
        beginMember()
          beginMethod(null, null, null, null, null, Foo)
            handleVoidKeyword(void)
            handleIdentifier(Foo, methodDeclaration)
            handleNoTypeVariables(()
            beginFormalParameters((, MemberKind.NonStaticMethod)
            endFormalParameters(0, (, ), MemberKind.NonStaticMethod)
            beginInitializers(:)
              beginInitializer(initializer)
                handleIdentifier(initializer, expression)
                handleNoTypeArguments(=)
                handleNoArguments(=)
                handleSend(initializer, =)
                handleLiteralBool(true)
                handleAssignmentExpression(=)
              endInitializer({)
            endInitializers(1, :, {)
            handleAsyncModifier(null, null)
            beginBlockFunctionBody({)
            endBlockFunctionBody(0, {, })
            handleRecoverableError(ConstructorWithReturnType, void, void)
          endClassConstructor(null, void, (, :, })
        endMember()
        beginMetadataStar(void)
        endMetadataStar(0)
        beginMember()
          beginMethod(null, null, null, null, null, Foo)
            handleVoidKeyword(void)
            handleIdentifier(Foo, methodDeclaration)
            handleIdentifier(x, methodDeclarationContinuation)
            handleQualified(.)
            handleNoTypeVariables(()
            beginFormalParameters((, MemberKind.NonStaticMethod)
            endFormalParameters(0, (, ), MemberKind.NonStaticMethod)
            handleNoInitializers()
            handleAsyncModifier(null, null)
            beginBlockFunctionBody({)
            endBlockFunctionBody(0, {, })
            handleRecoverableError(ConstructorWithReturnType, void, void)
          endClassConstructor(null, void, (, null, })
        endMember()
        beginMetadataStar(void)
        endMetadataStar(0)
        beginMember()
          beginMethod(null, null, null, null, null, Foo)
            handleVoidKeyword(void)
            handleIdentifier(Foo, methodDeclaration)
            handleIdentifier(x, methodDeclarationContinuation)
            handleQualified(.)
            handleNoTypeVariables(()
            beginFormalParameters((, MemberKind.NonStaticMethod)
            endFormalParameters(0, (, ), MemberKind.NonStaticMethod)
            beginInitializers(:)
              beginInitializer(initializer)
                handleIdentifier(initializer, expression)
                handleNoTypeArguments(=)
                handleNoArguments(=)
                handleSend(initializer, =)
                handleLiteralBool(true)
                handleAssignmentExpression(=)
              endInitializer({)
            endInitializers(1, :, {)
            handleAsyncModifier(null, null)
            beginBlockFunctionBody({)
            endBlockFunctionBody(0, {, })
            handleRecoverableError(ConstructorWithReturnType, void, void)
          endClassConstructor(null, void, (, :, })
        endMember()
      endClassOrMixinBody(DeclarationKind.Class, 4, {, })
    endClassDeclaration(class, })
  endTopLevelDeclaration()
endCompilationUnit(1, )