Share locals between members

pkg/compiler/lib/src/js_model/closure.dart

Index: pkg/compiler/lib/src/js_model/closure.dart
diff --git a/pkg/compiler/lib/src/js_model/closure.dart b/pkg/compiler/lib/src/js_model/closure.dart
index 153853ac9dc1b0c9b68e7d498e7b48d4c095e026..f0e06a513878a8b04ef0bd4f0977309cb153f772 100644
--- a/pkg/compiler/lib/src/js_model/closure.dart
+++ b/pkg/compiler/lib/src/js_model/closure.dart
@@ -139,6 +139,7 @@ class KernelClosureConversionTask extends ClosureConversionTask<ir.Node> {
     // We want the original declaration where that function is used to point
     // to the correct closure class.
     _closureRepresentationMap[closureClass.callMethod] = closureClass;
+    _globalLocalsMap.setLocalsMap(closureClass.callMethod, localsMap);

[Emily Fortuna, 2017/08/17 19:01:59]

what about grouping the locals map for all the created closures in ScopeModel
(like the capturedScopes)?

[Johnni Winther, 2017/08/18 14:59:39]

This line means we are sharing the map for all those closures. (Not sure what
you mean by 'grouping')

     Entity entity;
     if (node.parent is ir.Member) {
       entity = _elementMap.getMember(node.parent);
@@ -398,13 +399,7 @@ class NodeBox {
 }
 
 class JClosureClass extends JClass {
-  // TODO(efortuna): Storing this map here is so horrible. Instead store this on
-  // the ScopeModel (because all of the closures share that localsMap) and then
-  // set populate the getLocalVariable lookup with this localsMap for all the
-  // closures.
-  final KernelToLocalsMap localsMap;

[Emily Fortuna, 2017/08/17 19:01:59]

if we get rid of this field, all JClosureClasses can just become JClasses,
because there's no need to have a separate type of object. 

[Johnni Winther, 2017/08/18 14:59:39]

It does have a better to `toString` and the right [isClosure] value!

-
-  JClosureClass(this.localsMap, JLibrary library, int classIndex, String name)
+  JClosureClass(JLibrary library, int classIndex, String name)
       : super(library, classIndex, name, isAbstract: false);
 
   @override