Only create ScopeInfos for scopes that really need one

src/ast/scopes.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_AST_SCOPES_H_
 #define V8_AST_SCOPES_H_
 
 #include "src/base/hashmap.h"
 #include "src/globals.h"
 #include "src/objects.h"
@@ skipping 426 matching lines @@
 
   // This method should only be invoked on scopes created during parsing (i.e.,
   // not deserialized from a context). Also, since NeedsContext() is only
   // returning a valid result after variables are resolved, NeedsScopeInfo()
   // should also be invoked after resolution.
   bool NeedsScopeInfo() const {
     DCHECK(!already_resolved_);
     // A lazily parsed scope doesn't contain enough information to create a
     // ScopeInfo from it.
     if (is_lazily_parsed_) return false;
-    return NeedsContext() || is_script_scope() || is_function_scope() ||
-           is_eval_scope() || is_module_scope();
+    // The debugger expects all functions to have scope infos.
+    // TODO(jochen|yangguo): Remove this requirement.
+    if (is_function_scope()) return true;
+    return NeedsContext();
   }
 
   Zone* zone_;
 
   // Scope tree.
   Scope* outer_scope_;  // the immediately enclosing outer scope, or NULL
   Scope* inner_scope_;  // an inner scope of this scope
   Scope* sibling_;  // a sibling inner scope of the outer scope of this scope.
 
   // The variables declared in this scope:
@@ skipping 414 matching lines @@
   void AllocateModuleVariables();
 
  private:
   ModuleDescriptor* module_descriptor_;
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_AST_SCOPES_H_