Removed unused code path.

chrome/common/print_messages.h

 // Copyright (c) 2012 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.
 
 // IPC messages for printing.
 // Multiply-included message file, hence no include guard.
 
 #include <string>
 #include <vector>
 
@@ skipping 165 matching lines @@
   // Parameters to render the page as a printed page. It must always be the same
   // value for all the document.
   IPC_STRUCT_TRAITS_MEMBER(params)
 
   // If empty, this means a request to render all the printed pages.
   IPC_STRUCT_TRAITS_MEMBER(pages)
 IPC_STRUCT_TRAITS_END()
 
 // Parameters to describe a rendered document.
 IPC_STRUCT_BEGIN(PrintHostMsg_DidPreviewDocument_Params)
-  // True when we can reuse existing preview data. |metafile_data_handle| and
-  // |data_size| should not be used when this is true.
-  IPC_STRUCT_MEMBER(bool, reuse_existing_data)
-
   // A shared memory handle to metafile data.
   IPC_STRUCT_MEMBER(base::SharedMemoryHandle, metafile_data_handle)
 
   // Size of metafile data.
   IPC_STRUCT_MEMBER(uint32, data_size)
 
   // Cookie for the document to ensure correctness.
   IPC_STRUCT_MEMBER(int, document_cookie)
 
   // Store the expected pages count.
@@ skipping 235 matching lines @@
 IPC_SYNC_MESSAGE_ROUTED0_0(PrintHostMsg_SetupScriptedPrintPreview)
 
 // Tell the browser to show the print preview, when the document is sufficiently
 // loaded such that the renderer can determine whether it is modifiable or not.
 IPC_MESSAGE_ROUTED1(PrintHostMsg_ShowScriptedPrintPreview,
                     bool /* is_modifiable */)
 
 // Notify the browser that the PDF in the initiator renderer has disabled print
 // scaling option.
 IPC_MESSAGE_ROUTED0(PrintHostMsg_PrintPreviewScalingDisabled)