Move pre-declaring the this variable to Scope::Analyze

The goal is to not have to look at the outer scope chain during parsing.

BUG=v8:5215
R=verwaest@chromium.org,marja@chromium.org

Review-Url: https://codereview.chromium.org/2298673002
Cr-Commit-Position: refs/heads/master@{#39042}

src/ast/scopes.cc

@@ -420,6 +420,13 @@ void DeclarationScope::Analyze(ParseInfo* info, AnalyzeMode mode) {
          scope->outer_scope()->scope_type() == SCRIPT_SCOPE ||
          scope->outer_scope()->already_resolved_);
 
+  // If there's a chance that there's a reference to global 'this', predeclare
+  // it as a dynamic global on the script scope.
+  if (scope->GetReceiverScope()->is_script_scope()) {
+    info->script_scope()->DeclareDynamicGlobal(
+        info->ast_value_factory()->this_string(), Variable::THIS);
+  }
+
   scope->AllocateVariables(info, mode);
 
 #ifdef DEBUG

src/parsing/parser.cc

@@ -671,12 +671,6 @@ FunctionLiteral* Parser::DoParseProgram(ParseInfo* info) {
   {
     Scope* outer = original_scope_;
     DCHECK_NOT_NULL(outer);
-    // If there's a chance that there's a reference to global 'this', predeclare
-    // it as a dynamic global on the script scope.
-    if (outer->GetReceiverScope()->is_script_scope()) {
-      info->script_scope()->DeclareDynamicGlobal(
-          ast_value_factory()->this_string(), Variable::THIS);
-    }
     if (info->is_eval()) {
       if (!outer->is_script_scope() || is_strict(info->language_mode())) {
         parsing_mode = PARSE_EAGERLY;
@@ -841,12 +835,6 @@ FunctionLiteral* Parser::DoParseLazy(ParseInfo* info,
     // Parse the function literal.
     Scope* outer = original_scope_;
     DCHECK(outer);
-    // If there's a chance that there's a reference to global 'this', predeclare
-    // it as a dynamic global on the script scope.
-    if (info->is_arrow() && outer->GetReceiverScope()->is_script_scope()) {
-      info->script_scope()->DeclareDynamicGlobal(
-          ast_value_factory()->this_string(), Variable::THIS);
-    }
     FunctionState function_state(&function_state_, &scope_state_, outer,
                                  info->function_kind());
     DCHECK(is_sloppy(outer->language_mode()) ||