Force eager compilation of some function literals.

src/ast.h

Index: src/ast.h
diff --git a/src/ast.h b/src/ast.h
index 39756678dc807fb8a8bdd4bd378aebcf1132f7d7..32d87bd732d07c33318a7c8631a8487bdf9e7ea5 100644
--- a/src/ast.h
+++ b/src/ast.h
@@ -2091,9 +2091,17 @@ class FunctionLiteral: public Expression {
 
   bool is_function() { return IsFunction::decode(bitfield_) == kIsFunction; }
 
+  // This is used as a heuristic on when to eagerly compile a function
+  // literal. We consider the following constructs as hints that the
+  // function will be called immediately:
+  // - (function() { ... })();
+  // - var x = function() { ... }();
   bool is_parenthesized() {
     return IsParenthesized::decode(bitfield_) == kIsParenthesized;
   }
+  void set_parenthesized() {
+    bitfield_ = IsParenthesized::update(bitfield_, kIsParenthesized);
+  }
 
   int ast_node_count() { return ast_properties_.node_count(); }
   AstProperties::Flags* flags() { return ast_properties_.flags(); }