Preserve type variables in closure conversion.

pkg/kernel/testcases/closures/instance_tear_off.dart.expect

Index: pkg/kernel/testcases/closures/instance_tear_off.dart.expect
diff --git a/pkg/kernel/testcases/closures/instance_tear_off.dart.expect b/pkg/kernel/testcases/closures/instance_tear_off.dart.expect
index 2d8297742776b0d2a41ec79807736a5008296c6b..73609c79306cd35e17e1a2229db5c5e23ecf1aa5 100644
--- a/pkg/kernel/testcases/closures/instance_tear_off.dart.expect
+++ b/pkg/kernel/testcases/closures/instance_tear_off.dart.expect
@@ -50,7 +50,7 @@ class E<T extends core::Object> extends core::Object {
     : super core::Object::•()
     ;
   get g() → dynamic {
-    return MakeClosure<(dynamic) → dynamic>(self::closure#E#g#function, null);
+    return MakeClosure<<T extends core::Object>(T) → dynamic, self::E::T>(self::closure#E#g#function, null);
   }
   method a() → dynamic {
     return "a";
@@ -107,7 +107,7 @@ static method closure#D#g#function(Vector #contextParameter, dynamic x) → dyna
 static method closure#D#f#function(Vector #contextParameter) → dynamic {
   return "f";
 }
-static method closure#E#g#function(Vector #contextParameter, dynamic x) → dynamic {
+static method closure#E#g#function<T extends core::Object>(Vector #contextParameter, self::closure#E#g#function::T x) → dynamic {
   return "g(${x})";
 }
 static method closure#E#f#function(Vector #contextParameter) → dynamic {