[kernel] Support for top-level generic functions.

pkg/kernel/lib/transformations/closure/context.dart

Index: pkg/kernel/lib/transformations/closure/context.dart
diff --git a/pkg/kernel/lib/transformations/closure/context.dart b/pkg/kernel/lib/transformations/closure/context.dart
index 79ceaefde95039f55d449563d65171a32e4e1f4b..3e4ed1790904785fa56979252c480ee6682998b1 100644
--- a/pkg/kernel/lib/transformations/closure/context.dart
+++ b/pkg/kernel/lib/transformations/closure/context.dart
@@ -129,10 +129,11 @@ class LocalContext extends Context {
   Accessor get accessor => new VariableAccessor(self, null, TreeNode.noOffset);
 
   void extend(VariableDeclaration variable, Expression value) {
-    // Increase index by 1, because the parent occupies item 0, and all other
-    // variables are therefore shifted by 1.
+    // Increase index by 2, because the type arguments vector occupies position
+    // 0, the parent occupies position 1, and all other variables are therefore
+    // shifted by 2.
     VectorSet initializer =
-        new VectorSet(expression, variables.length + 1, value);
+        new VectorSet(expression, variables.length + 2, value);
     value.parent = initializer;
 
     converter.rewriter.insertExtendContext(initializer);
@@ -150,21 +151,23 @@ class LocalContext extends Context {
 
   Expression lookup(VariableDeclaration variable) {
     var index = variables.indexOf(variable);
-    // Increase index by 1 in case of success, because the parent occupies
-    // item 0, and all other variables are therefore shifted by 1.
+    // Increase index by 2 in case of success, because the type arguments vector
+    // occupies position 0, the parent occupies position 1, and all other
+    // variables are therefore shifted by 2.
     return index == -1
         ? parent.lookup(variable)
-        : new VectorGet(expression, index + 1);
+        : new VectorGet(expression, index + 2);
   }
 
   Expression assign(VariableDeclaration variable, Expression value,
       {bool voidContext: false}) {
     var index = variables.indexOf(variable);
-    // Increase index by 1 in case of success, because the parent occupies
-    // item 0, and all other variables are therefore shifted by 1.
+    // Increase index by 2 in case of success, because the type arguments vector
+    // occupies position 0, the parent occupies position 1, and all other
+    // variables are therefore shifted by 2.
     return index == -1
         ? parent.assign(variable, value, voidContext: voidContext)
-        : new VectorSet(expression, index + 1, value);
+        : new VectorSet(expression, index + 2, value);
   }
 
   Context toNestedContext([Accessor accessor]) {
@@ -210,12 +213,13 @@ class NestedContext extends Context {
     for (var variables in variabless) {
       var index = variables.indexOf(variable);
       if (index != -1) {
-        // Increase index by 1, because the parent occupies item 0, and all
-        // other variables are therefore shifted by 1.
-        return new VectorGet(context, index + 1);
+        // Increase index by 2 in case of success, because the type arguments
+        // vector occupies position 0, the parent occupies item 1, and all other
+        // variables are therefore shifted by 2.
+        return new VectorGet(context, index + 2);
       }
-      // Item 0 of a context always points to its parent.
-      context = new VectorGet(context, 0);
+      // Item 1 of a context always points to its parent.
+      context = new VectorGet(context, 1);
     }
     throw 'Unbound NestedContext.lookup($variable)';
   }
@@ -226,12 +230,13 @@ class NestedContext extends Context {
     for (List<VariableDeclaration> variables in variabless) {
       var index = variables.indexOf(variable);
       if (index != -1) {
-        // Increase index by 1, because the parent occupies item 0, and all
-        // other variables are therefore shifted by 1.
-        return new VectorSet(context, index + 1, value);
+        // Increase index by 2 in case of success, because the type arguments
+        // vector occupies position 0, the parent occupies item 1, and all other
+        // variables are therefore shifted by 2.
+        return new VectorSet(context, index + 2, value);
       }
-      // Item 0 of a context always points to its parent.
-      context = new VectorGet(context, 0);
+      // Item 1 of a context always points to its parent.
+      context = new VectorGet(context, 1);
     }
     throw 'Unbound NestedContext.lookup($variable)';
   }