Print Preview: Fixing behavior of event listeners.

chrome/common/print_messages.h

Index: chrome/common/print_messages.h
diff --git a/chrome/common/print_messages.h b/chrome/common/print_messages.h
index 618ece5b3ceffdf4cd6cec9996584dbb2da9378f..364f41ad6a1aa7c2d8b6fa8910c231b632d4ef32 100644
--- a/chrome/common/print_messages.h
+++ b/chrome/common/print_messages.h
@@ -107,6 +107,9 @@ IPC_STRUCT_BEGIN(PrintHostMsg_DidPreviewPage_Params)
   // |page_number| is zero-based and can be |printing::INVALID_PAGE_INDEX| if it
   // is just a check.
   IPC_STRUCT_MEMBER(int, page_number)
+
+  // The id of the preview request.
+  IPC_STRUCT_MEMBER(int, preview_request_id)
 IPC_STRUCT_END()
 
 // Parameters to describe a rendered page.
@@ -259,10 +262,11 @@ IPC_MESSAGE_CONTROL1(PrintHostMsg_TempFileForPrintingWritten,
 IPC_MESSAGE_ROUTED0(PrintHostMsg_RequestPrintPreview)
 
 // Notify the browser the number of pages in the print preview document.
-IPC_MESSAGE_ROUTED3(PrintHostMsg_DidGetPreviewPageCount,
+IPC_MESSAGE_ROUTED4(PrintHostMsg_DidGetPreviewPageCount,
                     int  /* document cookie */,
                     int  /* page count */,
-                    bool /* is modifiable */)
+                    bool /* is modifiable */,
+                    int  /* preview_request_id*/)
 
 // Notify the browser a print preview page has been rendered.
 IPC_MESSAGE_ROUTED1(PrintHostMsg_DidPreviewPage,