Use int64 time stamp when storing metadata to the HTTP cache.

content/common/view_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 page rendering.
 // Multiply-included message file, hence no include guard.
 
 #include "base/memory/shared_memory.h"
 #include "base/process/process.h"
 #include "base/strings/string16.h"
@@ skipping 1450 matching lines @@
 // Asks the browser process to generate a keypair for grabbing a client
 // certificate from a CA (<keygen> tag), and returns the signed public
 // key and challenge string.
 IPC_SYNC_MESSAGE_CONTROL3_1(ViewHostMsg_Keygen,
                             uint32 /* key size index */,
                             std::string /* challenge string */,
                             GURL /* URL of requestor */,
                             std::string /* signed public key and challenge */)
 
 // Message sent from the renderer to the browser to request that the browser
-// cache |data| associated with |url|.
+// cache |data| associated with |url| and |expected_response_time|.
 IPC_MESSAGE_CONTROL3(ViewHostMsg_DidGenerateCacheableMetadata,
                      GURL /* url */,
-                     double /* expected_response_time */,
+                     base::Time /* expected_response_time */,
                      std::vector<char> /* data */)
 
 // Register a new handler for URL requests with the given scheme.
 IPC_MESSAGE_ROUTED4(ViewHostMsg_RegisterProtocolHandler,
                     std::string /* scheme */,
                     GURL /* url */,
                     base::string16 /* title */,
                     bool /* user_gesture */)
 
 // Unregister the registered handler for URL requests with the given scheme.
@@ skipping 165 matching lines @@
 // cached by the OS. Please see RenderMessageFilter::OnPreCacheFontCharacters
 // for details.
 IPC_SYNC_MESSAGE_CONTROL2_0(ViewHostMsg_PreCacheFontCharacters,
                             LOGFONT /* font_data */,
                             base::string16 /* characters */)
 #endif
 
 // Adding a new message? Stick to the sort order above: first platform
 // independent ViewMsg, then ifdefs for platform specific ViewMsg, then platform
 // independent ViewHostMsg, then ifdefs for platform specific ViewHostMsg.