Fix for 'Simple Adblock' extension crashes

content/common/view_messages.h

Index: content/common/view_messages.h
diff --git a/content/common/view_messages.h b/content/common/view_messages.h
index 4688fd6494f44ec7d8067b56b4ed2091186d31b6..17683fea925be786179019d38e930c51078d440a 100644
--- a/content/common/view_messages.h
+++ b/content/common/view_messages.h
@@ -567,6 +567,7 @@ IPC_MESSAGE_ROUTED1(ViewMsg_UpdateWebPreferences,
 IPC_MESSAGE_CONTROL0(ViewMsg_TimezoneChange)
 
 // Tells the render view to close.
+// Expects a Close_ACK message when finished.
 IPC_MESSAGE_ROUTED0(ViewMsg_Close)
 
 IPC_STRUCT_BEGIN(ViewMsg_Resize_Params)
@@ -1101,6 +1102,11 @@ IPC_MESSAGE_ROUTED5(ViewHostMsg_Find_Reply,
                     int /* active_match_ordinal */,
                     bool /* final_update */)
 
+// Indicates that the render view has been closed in respose to a
+// Close message.
+IPC_MESSAGE_CONTROL1(ViewHostMsg_Close_ACK,
+                     int /* old_route_id */);
+
 // Indicates that the current page has been closed, after a ClosePage
 // message.
 IPC_MESSAGE_ROUTED0(ViewHostMsg_ClosePage_ACK)