SOLR-3140, omitNorms=true was made the default for all primitive fields. But this is not the case for TrieDateField - if the fieldType config for a TrieDateField has no omitNorms set, the fields will have norms.
It definitely looks like it was intended for TrieDateField to default to omitNorms=true, because in the example schema.xml, omitNorms=true was removed from tdate.
I think TrieDateField.init() just needs to call super.init() to fix this. Right now it is initializing its wrapped field, but not itself.
There were some changes around this in trunk in
SOLR-5936, but I haven't tested to see if it's fixed there. It might have covered this bug up even further, as there is now a test in PrimitiveFieldTypeTest for this, but it uses the overridden TrieDateField.hasProperty() method, which is not the way that SchemaField actually accesses the field type properties.