/usr/share/perl5/MooseX/Declare/Syntax/ is in libmoosex-declare-perl 0.38-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/perl5/MooseX/Declare/Syntax/EmptyBlockIfMissing.pm
/usr/share/perl5/MooseX/Declare/Syntax/Extending.pm
/usr/share/perl5/MooseX/Declare/Syntax/InnerSyntaxHandling.pm
/usr/share/perl5/MooseX/Declare/Syntax/Keyword/
/usr/share/perl5/MooseX/Declare/Syntax/Keyword/Class.pm
/usr/share/perl5/MooseX/Declare/Syntax/Keyword/Clean.pm
/usr/share/perl5/MooseX/Declare/Syntax/Keyword/Method.pm
/usr/share/perl5/MooseX/Declare/Syntax/Keyword/MethodModifier.pm
/usr/share/perl5/MooseX/Declare/Syntax/Keyword/Namespace.pm
/usr/share/perl5/MooseX/Declare/Syntax/Keyword/Role.pm
/usr/share/perl5/MooseX/Declare/Syntax/Keyword/With.pm
/usr/share/perl5/MooseX/Declare/Syntax/KeywordHandling.pm
/usr/share/perl5/MooseX/Declare/Syntax/MethodDeclaration/
/usr/share/perl5/MooseX/Declare/Syntax/MethodDeclaration.pm
/usr/share/perl5/MooseX/Declare/Syntax/MethodDeclaration/Parameterized.pm
/usr/share/perl5/MooseX/Declare/Syntax/MooseSetup.pm
/usr/share/perl5/MooseX/Declare/Syntax/NamespaceHandling.pm
/usr/share/perl5/MooseX/Declare/Syntax/OptionHandling.pm
/usr/share/perl5/MooseX/Declare/Syntax/RoleApplication.pm