Add primitive to create closures and use it for closure conversion

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

 library;
 import self as self;
 import "dart:core" as core;
 
-class Closure#f_1_1_no_default extends core::Object implements core::Function {
-  field core::String note = "This is temporary. The VM doesn't need closure classes.";
-  constructor •() → dynamic
-    ;
-  method call(dynamic a, [dynamic b]) → dynamic
-    return self::f_1_1_no_default(a, b);
-}
-class Closure#f_1_1_default extends core::Object implements core::Function {
-  field core::String note = "This is temporary. The VM doesn't need closure classes.";
-  constructor •() → dynamic
-    ;
-  method call(dynamic a, [dynamic b = 2]) → dynamic
-    return self::f_1_1_default(a, b);
-}
-class Closure#f_1_b_no_default extends core::Object implements core::Function {
-  field core::String note = "This is temporary. The VM doesn't need closure classes.";
-  constructor •() → dynamic
-    ;
-  method call(dynamic a, {dynamic b}) → dynamic
-    return self::f_1_b_no_default(a, b: b);
-}
-class Closure#f_1_b_default extends core::Object implements core::Function {
-  field core::String note = "This is temporary. The VM doesn't need closure classes.";
-  constructor •() → dynamic
-    ;
-  method call(dynamic a, {dynamic b = 2}) → dynamic
-    return self::f_1_b_default(a, b: b);
-}
 static method f_1_1_no_default(dynamic a, [dynamic b]) → dynamic {
   return a.+(b);
 }
 static method f_1_1_default(dynamic a, [dynamic b = 2]) → dynamic {
   return a.+(b);
 }
 static method f_1_b_no_default(dynamic a, {dynamic b}) → dynamic {
   return a.+(b);
 }
 static method f_1_b_default(dynamic a, {dynamic b = 2}) → dynamic {
@@ skipping 27 matching lines @@
       throw "Unexpected result: ${result}.";
   }
   else {
     if(!threw)
       throw "Expected exception missing.";
     if(!0.==(result))
       throw "Unexpected result: ${result}.";
   }
 }
 static method main(dynamic arguments) → dynamic {
-  self::test_1_1(new self::Closure#f_1_1_no_default::•(), false);
-  self::test_1_1(new self::Closure#f_1_1_default::•(), true);
-  self::test_1_b(new self::Closure#f_1_b_no_default::•(), false);
-  self::test_1_b(new self::Closure#f_1_b_default::•(), true);
+  self::test_1_1(MakeClosure<(dynamic, [dynamic]) → dynamic>(closure#f_1_1_no_default, null), false);
+  self::test_1_1(MakeClosure<(dynamic, [dynamic]) → dynamic>(closure#f_1_1_default, null), true);
+  self::test_1_b(MakeClosure<(dynamic, {b: dynamic}) → dynamic>(closure#f_1_b_no_default, null), false);
+  self::test_1_b(MakeClosure<(dynamic, {b: dynamic}) → dynamic>(closure#f_1_b_default, null), true);
 }
+static method closure#f_1_1_no_default(Vector #contextParameter, dynamic a, [dynamic b]) → dynamic
+  return self::f_1_1_no_default(a, b);
+static method closure#f_1_1_default(Vector #contextParameter, dynamic a, [dynamic b = 2]) → dynamic
+  return self::f_1_1_default(a, b);
+static method closure#f_1_b_no_default(Vector #contextParameter, dynamic a, {dynamic b}) → dynamic
+  return self::f_1_b_no_default(a, b: b);
+static method closure#f_1_b_default(Vector #contextParameter, dynamic a, {dynamic b = 2}) → dynamic
+  return self::f_1_b_default(a, b: b);