Recognize const/fixed/growable arrays in simple types inferrer.

sdk/lib/_internal/compiler/implementation/ssa/builder.dart

Index: sdk/lib/_internal/compiler/implementation/ssa/builder.dart
===================================================================
--- sdk/lib/_internal/compiler/implementation/ssa/builder.dart	(revision 19761)
+++ sdk/lib/_internal/compiler/implementation/ssa/builder.dart	(working copy)
@@ -3270,13 +3270,14 @@
     bool isListConstructor = false;
     computeType(element) {
       Element originalElement = elements[node];
-      if (identical(originalElement.getEnclosingClass(), compiler.listClass)) {
+      if (Elements.isFixedListConstructorCall(
+              originalElement, node, compiler)) {
         isListConstructor = true;
-        if (node.arguments.isEmpty) {
-          return HType.EXTENDABLE_ARRAY;
-        } else {
-          return HType.MUTABLE_ARRAY;

[kasperl, 2013/03/11 08:40:57]

Was this just pessimistic before?

[ngeoffray, 2013/03/11 08:59:57]

Yes it was. But the optimizers were putting it back to FIXED_LENGTH. I'm not
sure when and how we got that weird state. Frequent changes on the List class
lately may have created this situation.

-        }
+        return HType.FIXED_ARRAY;
+      } else if (Elements.isGrowableListConstructorCall(
+                    originalElement, node, compiler)) {
+        isListConstructor = true;
+        return HType.EXTENDABLE_ARRAY;
       } else if (element.isGenerativeConstructor()) {
         ClassElement cls = element.getEnclosingClass();
         return new HType.nonNullExact(cls.thisType, compiler);