[builtins] TurboFan version of Array.prototype.forEach including fast path for FAST_ELEMENTS

src/js/prologue.js

Index: src/js/prologue.js
diff --git a/src/js/prologue.js b/src/js/prologue.js
index e51ab558b6605e62d87b6be93ed9f34122f30e8b..df7370c33ed69fdfef593fb3864902d08267d68f 100644
--- a/src/js/prologue.js
+++ b/src/js/prologue.js
@@ -15,6 +15,11 @@ var imports = UNDEFINED;
 var imports_from_experimental = UNDEFINED;
 var exports_container = %ExportFromRuntime({});
 var typed_array_setup = UNDEFINED;
+var InstallExperimentalArrayFunctions;
+
+Import(function(from) {
+  InstallExperimentalArrayFunctions = from.InstallExperimentalArrayFunctions;
+});
 
 // Register context value to be initialized with a typed array in
 // Genesis::InitializeBuiltinTypedArrays.
@@ -86,14 +91,17 @@ function InstallConstants(object, constants) {
 }
 
 
-function InstallFunctions(object, attributes, functions) {
+  function InstallFunctions(object, attributes, functions,
+                            remove_prototype = true) {
   %CheckIsBootstrapping();
   %OptimizeObjectForAddingMultipleProperties(object, functions.length >> 1);
   for (var i = 0; i < functions.length; i += 2) {
     var key = functions[i];
     var f = functions[i + 1];
     SetFunctionName(f, key);
-    %FunctionRemovePrototype(f);
+    if (remove_prototype) {
+        %FunctionRemovePrototype(f);
+    }
     %AddNamedProperty(object, key, f, attributes);
     %SetNativeFlag(f);
   }
@@ -200,7 +208,6 @@ function PostNatives(utils) {
   utils.ImportFromExperimental = UNDEFINED;
 }
 
-
 function PostExperimentals(utils) {
   %CheckIsBootstrapping();
   %ExportExperimentalFromRuntime(exports_container);
@@ -216,6 +223,8 @@ function PostExperimentals(utils) {
   utils.PostDebug = UNDEFINED;
   utils.PostExperimentals = UNDEFINED;
   typed_array_setup = UNDEFINED;
+
+  InstallExperimentalArrayFunctions();
 }