[runtime] Intercept function declarations.

src/runtime/runtime-scopes.cc

Index: src/runtime/runtime-scopes.cc
diff --git a/src/runtime/runtime-scopes.cc b/src/runtime/runtime-scopes.cc
index c0b7efe1dca13d53843a6a3d5423764817baf381..92dfcad66ec78a9c55e143663434e5140fdd2509 100644
--- a/src/runtime/runtime-scopes.cc
+++ b/src/runtime/runtime-scopes.cc
@@ -44,7 +44,7 @@ Object* ThrowRedeclarationError(Isolate* isolate, Handle<String> name,
 Object* DeclareGlobal(
     Isolate* isolate, Handle<JSGlobalObject> global, Handle<String> name,
     Handle<Object> value, PropertyAttributes attr, bool is_var,
-    bool is_function, RedeclarationType redeclaration_type,
+    bool is_function_declaration, RedeclarationType redeclaration_type,
     Handle<TypeFeedbackVector> feedback_vector = Handle<TypeFeedbackVector>(),
     FeedbackVectorSlot slot = FeedbackVectorSlot::Invalid()) {
   Handle<ScriptContextTable> script_contexts(
@@ -60,7 +60,14 @@ Object* DeclareGlobal(
   }
 
   // Do the lookup own properties only, see ES5 erratum.
-  LookupIterator it(global, name, global, LookupIterator::OWN_SKIP_INTERCEPTOR);
+  LookupIterator::Configuration lookup_config(
+      LookupIterator::Configuration::OWN_SKIP_INTERCEPTOR);
+  if (is_function_declaration) {
+    // For function declarations, use the interceptor on the declaration. For
+    // non-functions, use it only on initialization.
+    lookup_config = LookupIterator::Configuration::OWN;
+  }
+  LookupIterator it(global, name, global, lookup_config);
   Maybe<PropertyAttributes> maybe = JSReceiver::GetPropertyAttributes(&it);
   if (!maybe.IsJust()) return isolate->heap()->exception();
 
@@ -71,7 +78,7 @@ Object* DeclareGlobal(
     // Skip var re-declarations.
     if (is_var) return isolate->heap()->undefined_value();
 
-    DCHECK(is_function);
+    DCHECK(is_function_declaration);
     if ((old_attributes & DONT_DELETE) != 0) {
       // Only allow reconfiguring globals to functions in user code (no
       // natives, which are marked as read-only).
@@ -83,9 +90,9 @@ Object* DeclareGlobal(
       if (old_details.IsReadOnly() || old_details.IsDontEnum() ||
           (it.state() == LookupIterator::ACCESSOR &&
            it.GetAccessors()->IsAccessorPair())) {
-        // ES#sec-globaldeclarationinstantiation 5.d:
+        // ECMA-262 section 15.1.11 GlobalDeclarationInstantiation 5.d:
         // If hasRestrictedGlobal is true, throw a SyntaxError exception.
-        // ES#sec-evaldeclarationinstantiation 8.a.iv.1.b:
+        // ECMA-262 section 18.2.1.3 EvalDeclarationInstantiation 8.a.iv.1.b:
         // If fnDefinable is false, throw a TypeError exception.
         return ThrowRedeclarationError(isolate, name, redeclaration_type);
       }
@@ -102,6 +109,10 @@ Object* DeclareGlobal(
     if (it.state() == LookupIterator::ACCESSOR) it.Delete();
   }
 
+  if (is_function_declaration) {
+    it.Restart();
+  }
+
   // Define or redefine own property.
   RETURN_FAILURE_ON_EXCEPTION(
       isolate, JSObject::DefineOwnPropertyIgnoreAttributes(&it, value, attr));