Implement proper scoping for "this" in arrow functions

src/compiler/ast-graph-builder.cc

Index: src/compiler/ast-graph-builder.cc
diff --git a/src/compiler/ast-graph-builder.cc b/src/compiler/ast-graph-builder.cc
index b6c6e0fb3f5bc1a0f396d178d09931f978332bda..00cdfe29b3784c505ccd1ff43810b20dbffc6e62 100644
--- a/src/compiler/ast-graph-builder.cc
+++ b/src/compiler/ast-graph-builder.cc
@@ -458,9 +458,11 @@ bool AstGraphBuilder::CreateGraph(bool constant_context) {
 
   // Build receiver check for sloppy mode if necessary.
   // TODO(mstarzinger/verwaest): Should this be moved back into the CallIC?
-  Node* original_receiver = env.Lookup(scope->receiver());
-  Node* patched_receiver = BuildPatchReceiverToGlobalProxy(original_receiver);
-  env.Bind(scope->receiver(), patched_receiver);
+  if (scope->has_this_declaration()) {
+    Node* original_receiver = env.Lookup(scope->receiver());
+    Node* patched_receiver = BuildPatchReceiverToGlobalProxy(original_receiver);
+    env.Bind(scope->receiver(), patched_receiver);
+  }
 
   // Build function context only if there are context allocated variables.
   int heap_slots = info()->num_heap_slots() - Context::MIN_CONTEXT_SLOTS;
@@ -2457,8 +2459,10 @@ Node* AstGraphBuilder::BuildLocalFunctionContext(Node* context, Node* closure) {
 
   // Copy parameters into context if necessary.
   int num_parameters = info()->scope()->num_parameters();
-  for (int i = 0; i < num_parameters; i++) {
-    Variable* variable = info()->scope()->parameter(i);
+  int first_parameter = info()->scope()->has_this_declaration() ? -1 : 0;
+  for (int i = first_parameter; i < num_parameters; i++) {
+    Variable* variable =
+        (i == -1) ? info()->scope()->receiver() : info()->scope()->parameter(i);
     if (!variable->IsContextSlot()) continue;
     // Temporary parameter node. The parameter indices are shifted by 1
     // (receiver is parameter index -1 but environment index 0).