AppCache: Defend against bad IPC messages.

content/browser/appcache/appcache_host.h

Index: content/browser/appcache/appcache_host.h
diff --git a/content/browser/appcache/appcache_host.h b/content/browser/appcache/appcache_host.h
index 7525ea2f7b8980513c3a0334690f73b2f35421f2..f43952006f7d69a44406399106cbd063f4e097ae 100644
--- a/content/browser/appcache/appcache_host.h
+++ b/content/browser/appcache/appcache_host.h
@@ -163,6 +163,7 @@ class CONTENT_EXPORT AppCacheHost
   AppCacheStorage* storage() const { return storage_; }
   AppCacheFrontend* frontend() const { return frontend_; }
   AppCache* associated_cache() const { return associated_cache_.get(); }
+  bool was_select_cache_called() const { return was_select_cache_called_; }
 
   void enable_cache_selection(bool enable) {
     is_cache_selection_enabled_ = enable;
@@ -269,6 +270,9 @@ class CONTENT_EXPORT AppCacheHost
   int64 pending_selected_cache_id_;
   GURL pending_selected_manifest_url_;
 
+  // Used to defend against bad IPC messages.
+  bool was_select_cache_called_;
+
   // Used to avoid stepping on pages controlled by ServiceWorkers.
   bool is_cache_selection_enabled_;