JS: removed unused JsContext methods

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsContext.java

@@ -12,16 +12,11 @@ import org.jetbrains.annotations.Nullable;
  * node.
  */
 public abstract class JsContext<T extends JsNode> {
-  public abstract boolean canInsert();
-
-  public abstract boolean canRemove();
 
   public abstract <R extends T> void insertAfter(R node);
 
   public abstract <R extends T> void insertBefore(R node);
 
-  public abstract boolean isLvalue();
-
   public abstract void removeMe();
 
   public abstract <R extends T> void replaceMe(R node);

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsVisitorWithContextImpl.java

@@ -40,16 +40,6 @@ public class JsVisitorWithContextImpl extends JsVisitorWithContext {
         private List<T> collection;
         private int index;
 
-        @Override
-        public boolean canInsert() {
-            return true;
-        }
-
-        @Override
-        public boolean canRemove() {
-            return true;
-        }
-
         @Override
         public <R extends T> void insertAfter(R node) {
             //noinspection unchecked
@@ -62,11 +52,6 @@ public class JsVisitorWithContextImpl extends JsVisitorWithContext {
             collection.add(index++, (T) node);
         }
 
-        @Override
-        public boolean isLvalue() {
-            return false;
-        }
-
         @Override
         public void removeMe() {
             collection.remove(index--);
@@ -98,25 +83,11 @@ public class JsVisitorWithContextImpl extends JsVisitorWithContext {
     }
 
     private class LvalueContext extends NodeContext<JsExpression> {
-        @Override
-        public boolean isLvalue() {
-            return true;
-        }
     }
 
     private class NodeContext<T extends JsNode> extends JsContext<T> {
         protected T node;
 
-        @Override
-        public boolean canInsert() {
-            return false;
-        }
-
-        @Override
-        public boolean canRemove() {
-            return false;
-        }
-
         @Override
         public <R extends T> void insertAfter(R node) {
             throw new UnsupportedOperationException();
@@ -127,11 +98,6 @@ public class JsVisitorWithContextImpl extends JsVisitorWithContext {
             throw new UnsupportedOperationException();
         }
 
-        @Override
-        public boolean isLvalue() {
-            return false;
-        }
-
         @Override
         public void removeMe() {
             throw new UnsupportedOperationException();