private boolean activateEquivalenceCache() {
		EquivalenceCache cache = equivalenceCache.get();
		if (cache == null) {
			cache = new EquivalenceCache();
			equivalenceCache.set(cache);
			cache.putValue(0, null); // keep cache active until cleared
			return true;
		}
		return false;
	}
Perform forced activation of equivalence cache if not already active. If true
is returned, cache will remain active until {@link #clearEquivalenceCache()}
is invoked.

@return true if successful, false if already active
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/data/DataTypeManagerDB.java