protected boolean doSetPrimary(boolean primary) {
		boolean old = isPrimary();
		if (primary == old) {
			return false;
		}
		if (primary) {
			flags |= PRIMARY_MASK;
		}
		else {
			flags &= PRIMARY_CLEAR;
		}
		return true;
	}
Set the primary flag.

The caller must still call {@link #update(DBObjectColumn...)} for {@link #FLAGS_COLUMN}, if
this method returns true.

@return true if the primary flag was modified.
Ghidra/Debug/Framework-TraceModeling/src/main/java/ghidra/trace/database/symbol/DBTraceLabelSymbol.java