TokenTreeBuilder crash with Map / Hash conditional

[Gama11]

This sort of thing is seen every now and then for backwards-compatibility with Haxe 2:

class Foo {
    var library = new #if haxe3 Map<String, #else Hash <#end String>();
}

./source/Test.hx:2: characters 58-64: bad token Const(CIdent(String)) != POpen
Stacktrace: 
Called from checkstyle.token.TokenStream::consumeTokenDef line 50
Called from checkstyle.token.walk.WalkPOpen::walkPOpen line 13
Called from checkstyle.token.walk.WalkNew::walkNew line 15
Called from checkstyle.token.walk.WalkStatement::walkKeyword line 107
Called from checkstyle.token.walk.WalkStatement::walkStatement line 37
Called from checkstyle.token.walk.WalkStatement::walkStatement line 73
Called from checkstyle.token.walk.WalkVar::walkVar line 30
Called from checkstyle.token.walk.WalkClass::walkClass line 32
Called from checkstyle.token.walk.WalkType::walkType line 14
Called from checkstyle.token.walk.WalkFile::walkFile line 27
Called from checkstyle.token.TokenTreeBuilder::buildTokenTree line 14
Called from checkstyle.Checker::getTokenTree line 55
Called from checkstyle.checks.whitespace.WhitespaceAfterCheck::checkTokens line 88
Called from checkstyle.checks.whitespace.WhitespaceAfterCheck::actualRun line 84
Called from checkstyle.checks.Check::run line 41