Fix some egregious bugs in Var.

ppapi/cpp/var.h

 // Copyright (c) 2011 The Chromium 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 PPAPI_CPP_VAR_H_
 #define PPAPI_CPP_VAR_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 239 matching lines @@
   ///
   /// Example:
   ///   void FooBar(a, b, Var* exception = NULL) {
   ///     foo_interface->Bar(a, b, Var::OutException(exception).get());
   ///   }
   class OutException {
    public:
     /// A constructor.
     OutException(Var* v)
         : output_(v),
-          originally_had_exception_(v && v->is_null()) {
+          originally_had_exception_(v && !v->is_undefined()) {

[brettw, 2011/08/04 23:10:50]

It sucks this is in two places, I filed
http://code.google.com/p/chromium/issues/detail?id=91751 for this

       if (output_) {
         temp_ = output_->var_;
       } else {
         temp_.padding = 0;
         temp_.type = PP_VARTYPE_UNDEFINED;
       }
     }
 
     /// Destructor.
     ~OutException() {
@@ skipping 21 matching lines @@
   // Prevent an arbitrary pointer argument from being implicitly converted to
   // a bool at Var construction. If somebody makes such a mistake, (s)he will
   // get a compilation error.
   Var(void* non_scriptable_object_pointer);
 
 };
 
 }  // namespace pp
 
 #endif  // PPAPI_CPP_VAR_H_