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

content/child/web_url_loader_impl.cc

Index: content/child/web_url_loader_impl.cc
diff --git a/content/child/web_url_loader_impl.cc b/content/child/web_url_loader_impl.cc
index adca0daa2168438986daa602ed441b8934def803..b481779855bd0b0ad64481d8c225ec5bab38d89f 100644
--- a/content/child/web_url_loader_impl.cc
+++ b/content/child/web_url_loader_impl.cc
@@ -974,6 +974,8 @@ void WebURLLoaderImpl::PopulateURLResponse(const GURL& url,
                                            WebURLResponse* response) {
   response->setURL(url);
   response->setResponseTime(info.response_time.ToDoubleT());
+  response->setResponseTime(
+      static_cast<long long>(info.response_time.ToInternalValue()));

[Yang, 2015/02/19 08:39:44]

This static_cast will be removed in part 4 once the overloaded
setResponseTime(double) is removed in part 3.

   response->setMIMEType(WebString::fromUTF8(info.mime_type));
   response->setTextEncodingName(WebString::fromUTF8(info.charset));
   response->setExpectedContentLength(info.content_length);