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

Index: sdk/lib/_internal/compiler/implementation/closure.dart
===================================================================
--- sdk/lib/_internal/compiler/implementation/closure.dart	(revision 28922)
+++ sdk/lib/_internal/compiler/implementation/closure.dart	(working copy)
@@ -770,19 +770,13 @@
       }
 
       DartType type = element.computeType(compiler);
-      // Compute the function type and check for type variables in return or
-      // parameter types.
-      if (type.containsTypeVariables) {
-        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);
       }
-      // 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();
-      }
 
       visitChildren();
     });