Reapply "This change makes it easier to put type parameters on JavaScript Arrays."

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

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of ssa;
 
 /**
  * A special element for the extra parameter taken by intercepted
  * methods. We need to override [Element.computeType] because our
  * optimizers may look at its declared type.
@@ skipping 3770 matching lines @@
     pushInvokeStatic(
         null,
         typeInfoSetterElement,
         <HInstruction>[newObject, typeInfo],
         backend.dynamicType);
     pop();
   }
 
   handleNewSend(NewExpression node) {
     Send send = node.send;
-    bool isListConstructor = false;
     bool isFixedList = false;
 
     TypeMask computeType(element) {
       Element originalElement = elements[send];
       if (Elements.isFixedListConstructorCall(originalElement, send, compiler)
           || Elements.isFilledListConstructorCall(
                   originalElement, send, compiler)) {
-        isListConstructor = true;
         isFixedList = true;
         TypeMask inferred =
             TypeMaskFactory.inferredForNode(currentElement, send, compiler);
         return inferred.containsAll(compiler)
             ? backend.fixedArrayType
             : inferred;
       } else if (Elements.isGrowableListConstructorCall(
                     originalElement, send, compiler)) {
-        isListConstructor = true;
         TypeMask inferred =
             TypeMaskFactory.inferredForNode(currentElement, send, compiler);
         return inferred.containsAll(compiler)
             ? backend.extendableArrayType
             : inferred;
       } else if (Elements.isConstructorOfTypedArraySubclass(
                     originalElement, compiler)) {
         isFixedList = true;
         TypeMask inferred =
             TypeMaskFactory.inferredForNode(currentElement, send, compiler);
@@ skipping 10 matching lines @@
       }
     }
 
     Element constructor = elements[send];
     Selector selector = elements.getSelector(send);
     FunctionElement functionElement = constructor;
     constructor = functionElement.redirectionTarget;
 
     final bool isSymbolConstructor =
         functionElement == compiler.symbolConstructor;
+    final bool isJSArrayTypedConstructor =
+        functionElement == backend.jsArrayTypedConstructor;
 
     if (isSymbolConstructor) {
       constructor = compiler.symbolValidatedConstructor;
       assert(invariant(send, constructor != null,
                        message: 'Constructor Symbol.validated is missing'));
       selector = compiler.symbolValidatedConstructorSelector;
       assert(invariant(send, selector != null,
                        message: 'Constructor Symbol.validated is missing'));
     }
 
@@ skipping 45 matching lines @@
 
     if (isFixedList) {
       JavaScriptItemCompilationContext context = work.compilationContext;
       context.allocatedFixedLists.add(newInstance);
     }
 
     // The List constructor forwards to a Dart static method that does
     // not know about the type argument. Therefore we special case
     // this constructor to have the setRuntimeTypeInfo called where
     // the 'new' is done.
-    if (isListConstructor && backend.classNeedsRti(compiler.listClass)) {
+    if (isJSArrayTypedConstructor &&
+        backend.classNeedsRti(compiler.listClass)) {
       handleListConstructor(type, send, newInstance);
     }
 
     // Finally, if we called a redirecting factory constructor, check the type.
     if (isRedirected) {
       HInstruction checked = potentiallyCheckType(newInstance, type);
       if (checked != newInstance) {
         pop();
         stack.add(checked);
       }
@@ skipping 1974 matching lines @@
           new HSubGraphBlockInformation(elseBranch.graph));
 
     HBasicBlock conditionStartBlock = conditionBranch.block;
     conditionStartBlock.setBlockFlow(info, joinBlock);
     SubGraph conditionGraph = conditionBranch.graph;
     HIf branch = conditionGraph.end.last;
     assert(branch is HIf);
     branch.blockInformation = conditionStartBlock.blockFlow;
   }
 }