Added toString() implementations.

compiler/frontend/src/org/jetbrains/jet/lang/resolve/calls/tasks/ResolutionCandidate.java

@@ -106,4 +106,9 @@ public class ResolutionCandidate<D extends CallableDescriptor> {
         assert isSafeCall != null;
         return isSafeCall;
     }
+
+    @Override
+    public String toString() {
+        return candidateDescriptor.toString();
+    }
 }

compiler/frontend/src/org/jetbrains/jet/lang/resolve/calls/tasks/ResolutionTask.java

@@ -109,4 +109,9 @@ public class ResolutionTask<D extends CallableDescriptor, F extends D> extends C
     public interface DescriptorCheckStrategy {
         <D extends CallableDescriptor> boolean performAdvancedChecks(D descriptor, BindingTrace trace, TracingStrategy tracing);
     }
+
+    @Override
+    public String toString() {
+        return candidates.toString();
+    }
 }