Fix crash https://code.google.com/p/dart/issues/detail?id=14014: remove what seems to be obsolete c…

sdk/lib/_internal/compiler/implementation/closure.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library closureToClassMapper;
 
 import "elements/elements.dart";
 import "dart2jslib.dart";
 import "dart_types.dart";
 import "scanner/scannerlib.dart" show Token;
@@ skipping 752 matching lines @@
           compiler.backend.classNeedsRti(currentElement.enclosingElement)) {
         // Declare the type parameters in the scope. Generative
         // constructors just use 'this'.
         ClassElement cls = currentElement.enclosingElement;
         cls.typeVariables.forEach((TypeVariableType typeVariable) {
           declareLocal(typeVariable.element);
         });
       }
 
       DartType type = element.computeType(compiler);
-      // Compute the function type and check for type variables in return or
-      // parameter types.
-      if (type.containsTypeVariables) {
-        registerNeedsThis();
-      }
-      // Ensure that closure that need runtime type information has access to
-      // this of the enclosing class.
-      if (element is FunctionElement &&
-          closureData.thisElement != null &&
-          type.containsTypeVariables &&
-          compiler.backend.methodNeedsRti(element)) {
-        registerNeedsThis();
+      // If the method needs RTI, or checked mode is set, we need to
+      // escape the potential type variables used in that closure.
+      if (element is FunctionElement
+          && (compiler.backend.methodNeedsRti(element) ||
+              compiler.enableTypeAssertions)) {
+        analyzeTypeVariables(type);
       }
 
       visitChildren();
     });
 
 
     ClosureClassMap savedClosureData = closureData;
     bool savedInsideClosure = insideClosure;
 
     // Restore old values.
@@ skipping 39 matching lines @@
   }
 
   visitTryStatement(TryStatement node) {
     // TODO(ngeoffray): implement finer grain state.
     bool oldInTryStatement = inTryStatement;
     inTryStatement = true;
     node.visitChildren(this);
     inTryStatement = oldInTryStatement;
   }
 }