Fix scope flags for default parameters

src/parsing/parser.cc

Index: src/parsing/parser.cc
diff --git a/src/parsing/parser.cc b/src/parsing/parser.cc
index 50d875feb687347ca72b2f163f3ae84750105911..8164c7d3b2cda7e9dd5af74dac0883f0ff95541e 100644
--- a/src/parsing/parser.cc
+++ b/src/parsing/parser.cc
@@ -4554,6 +4554,7 @@ Block* Parser::BuildParameterInitializationBlock(
   DCHECK(scope_->is_function_scope());
   Block* init_block =
       factory()->NewBlock(NULL, 1, true, RelocInfo::kNoPosition);
+  ZoneList<Scope*>* param_scopes = new (zone()) ZoneList<Scope*>(0, zone());
   for (int i = 0; i < parameters.params.length(); ++i) {
     auto parameter = parameters.params[i];
     if (parameter.is_rest && parameter.pattern->IsVariableProxy()) break;
@@ -4595,12 +4596,13 @@ Block* Parser::BuildParameterInitializationBlock(
 
     Scope* param_scope = scope_;
     Block* param_block = init_block;
-    if (!parameter.is_simple() && scope_->calls_sloppy_eval()) {
+    if (!parameter.is_simple()) {
       param_scope = NewScope(scope_, BLOCK_SCOPE);
       param_scope->set_is_declaration_scope();
       param_scope->set_start_position(descriptor.initialization_pos);
       param_scope->set_end_position(parameter.initializer_end_position);
-      param_scope->RecordEvalCall();
+      param_scopes->Add(param_scope, zone());
+      scope_->PropagateUsageFlagsToScope(param_scope);

[adamk, 2016/06/06 18:53:36]

This is where we have to make the call, so that the call to FinalizeBlockScope
below doesn't over-eagerly remove this scope from the scope chain.

       param_block = factory()->NewBlock(NULL, 8, true, RelocInfo::kNoPosition);
       param_block->set_scope(param_scope);
       descriptor.hoist_scope = scope_;
@@ -4614,7 +4616,7 @@ Block* Parser::BuildParameterInitializationBlock(
                                                      &decl, nullptr, CHECK_OK);
     }
 
-    if (!parameter.is_simple() && scope_->calls_sloppy_eval()) {
+    if (!parameter.is_simple()) {
       param_scope = param_scope->FinalizeBlockScope();
       if (param_scope != nullptr) {
         CheckConflictingVarDeclarations(param_scope, CHECK_OK);
@@ -4622,6 +4624,9 @@ Block* Parser::BuildParameterInitializationBlock(
       init_block->statements()->Add(param_block, zone());
     }
   }
+  for (Scope* param_scope : *param_scopes) {
+    scope_->PropagateUsageFlagsToScope(param_scope);

[adamk, 2016/06/06 18:53:36]

This call is now redundant, right?

+  }
   return init_block;
 }