ppapi: Work around a compiler bug where the PPP_Printing_Dev struct is not zeroed out.

webkit/plugins/ppapi/ppapi_plugin_instance.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 WEBKIT_PLUGINS_PPAPI_PPAPI_PLUGIN_INSTANCE_H_
 #define WEBKIT_PLUGINS_PPAPI_PPAPI_PLUGIN_INSTANCE_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 409 matching lines @@
     PPP_Printing_Dev_Combined(const PPP_Printing_Dev& base_if)
         : PPP_Printing_Dev(base_if),
           QuerySupportedFormats_0_3(NULL),
           Begin_0_3(NULL) {}
 
     // Conversion constructor for version 0.3.  Sets unsupported functions to
     // NULL, so we know not to try to use them.
     PPP_Printing_Dev_Combined(const PPP_Printing_Dev_0_3& old_if)
         : PPP_Printing_Dev(),  // NOTE: The parens are important, to zero-
                                // initialize the struct.
+                               // Except older version of g++ doesn't!
+                               // So do it explicitly in the ctor.
           QuerySupportedFormats_0_3(old_if.QuerySupportedFormats),
           Begin_0_3(old_if.Begin) {
+      QuerySupportedFormats = NULL;
+      Begin = NULL;
       PrintPages = old_if.PrintPages;
       End = old_if.End;
     }
 
     // The 0.3 version of 'QuerySupportedFormats'.
     PP_PrintOutputFormat_Dev_0_3* (*QuerySupportedFormats_0_3)(
         PP_Instance instance, uint32_t* format_count);
     // The 0.3 version of 'Begin'.
     int32_t (*Begin_0_3)(PP_Instance instance,
                          const struct PP_PrintSettings_Dev_0_3* print_settings);
-
   };
   scoped_ptr<PPP_Printing_Dev_Combined> plugin_print_interface_;
 
   // The plugin 3D interface.
   const PPP_Graphics3D_Dev* plugin_graphics_3d_interface_;
 
   // Contains the cursor if it's set by the plugin.
   scoped_ptr<WebKit::WebCursorInfo> cursor_;
 
   // Set to true if this plugin thinks it will always be on top. This allows us
@@ skipping 23 matching lines @@
   typedef std::map<NPObject*, ObjectVar*> NPObjectToObjectVarMap;
   NPObjectToObjectVarMap np_object_to_object_var_;
 
   DISALLOW_COPY_AND_ASSIGN(PluginInstance);
 };
 
 }  // namespace ppapi
 }  // namespace webkit
 
 #endif  // WEBKIT_PLUGINS_PPAPI_PPAPI_PLUGIN_INSTANCE_H_