Use index in J/KTypeVariable and fix remaining inequivalence

pkg/compiler/lib/src/kernel/kelements.dart

Index: pkg/compiler/lib/src/kernel/kelements.dart
diff --git a/pkg/compiler/lib/src/kernel/kelements.dart b/pkg/compiler/lib/src/kernel/kelements.dart
index b72947a5635e75b93e811e64801b4db915478832..ba7b150f932f01ebad6011d40b7ae464f6d53b1e 100644
--- a/pkg/compiler/lib/src/kernel/kelements.dart
+++ b/pkg/compiler/lib/src/kernel/kelements.dart
@@ -229,11 +229,13 @@ class KField extends KMember implements FieldEntity, IndexedField {
 }
 
 class KTypeVariable implements TypeVariableEntity, IndexedTypeVariable {
+  final int typeVariableIndex;
   final Entity typeDeclaration;
   final String name;
   final int index;
 
-  KTypeVariable(this.typeDeclaration, this.name, this.index);
+  KTypeVariable(
+      this.typeVariableIndex, this.typeDeclaration, this.name, this.index);
 
   String toString() =>
       '${kElementPrefix}type_variable(${typeDeclaration.name}.$name)';