more toString impls to simplify debugging

java/debugger/impl/src/com/intellij/debugger/engine/evaluation/expression/AssignmentEvaluator.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2009 JetBrains s.r.o.
+ * Copyright 2000-2015 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -82,4 +82,9 @@ public class AssignmentEvaluator implements Evaluator{
   public Modifier getModifier() {
     return myLeftEvaluator.getModifier();
   }
+
+  @Override
+  public String toString() {
+    return myLeftEvaluator + " = " + myRightEvaluator;
+  }
 }

java/debugger/impl/src/com/intellij/debugger/engine/evaluation/expression/ThisEvaluator.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2009 JetBrains s.r.o.
+ * Copyright 2000-2015 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -79,4 +79,9 @@ public class ThisEvaluator implements Evaluator {
     }
     return null;
   }
+
+  @Override
+  public String toString() {
+    return "this";
+  }
 }