Added clarifying comments in toString()

compiler/frontend/serialization/src/org/jetbrains/jet/descriptors/serialization/descriptors/DeserializedClassDescriptor.java

@@ -294,6 +294,7 @@ public class DeserializedClassDescriptor extends AbstractClassDescriptor impleme
 
     @Override
     public String toString() {
+        // not using descriptor render to preserve laziness
         return "deserialized class " + getName().toString();
     }
 

compiler/frontend/src/org/jetbrains/jet/lang/resolve/lazy/descriptors/LazyClassDescriptor.java

@@ -316,6 +316,7 @@ public class LazyClassDescriptor extends ClassDescriptorBase implements LazyDesc
 
     @Override
     public String toString() {
+        // not using descriptor render to preserve laziness
         return "lazy class " + getName().toString();
     }