This is part of adding a new conformance rule to add additional type
safety. This will disallow using properties of unknown types or using
unknown properties.
The first parts will be fixing errors caused by the new rule. These
are backwards compatible, so can be applied before the rule is enabled.
Once all the errors and bugs are fixed, the rule will be enabled.
Change-Id: Ic37437a1ad2305bc50a814cdcc562e74703222ac