Cache failover to LOAD_PREFERRING_CACHE if network response suggests offline.

net/http/http_response_info.cc

Index: net/http/http_response_info.cc
diff --git a/net/http/http_response_info.cc b/net/http/http_response_info.cc
index 9c33ab4f53e8b0bef1ef03cb6c82cf16f7b6152a..a70f1403489a6f838ef2b3c5fb868c1e4d39b1b9 100644
--- a/net/http/http_response_info.cc
+++ b/net/http/http_response_info.cc
@@ -81,12 +81,17 @@ enum {
   // This bit is set if the response info has protocol version.
   RESPONSE_INFO_HAS_NPN_NEGOTIATED_PROTOCOL = 1 << 17,
 
+  // This bit is set if the request was overriden from cache due to
+  // various load flags being set.
+  RESPONSE_INFO_WAS_CACHE_OVERRIDE = 1 << 18,
+
   // TODO(darin): Add other bits to indicate alternate request methods.
   // For now, we don't support storing those.
 };
 
 HttpResponseInfo::HttpResponseInfo()
     : was_cached(false),
+      was_cache_override(false),
       was_fetched_via_spdy(false),
       was_npn_negotiated(false),
       was_fetched_via_proxy(false) {
@@ -94,6 +99,7 @@ HttpResponseInfo::HttpResponseInfo()
 
 HttpResponseInfo::HttpResponseInfo(const HttpResponseInfo& rhs)
     : was_cached(rhs.was_cached),
+      was_cache_override(rhs.was_cache_override),
       was_fetched_via_spdy(rhs.was_fetched_via_spdy),
       was_npn_negotiated(rhs.was_npn_negotiated),
       was_fetched_via_proxy(rhs.was_fetched_via_proxy),
@@ -114,6 +120,7 @@ HttpResponseInfo::~HttpResponseInfo() {
 
 HttpResponseInfo& HttpResponseInfo::operator=(const HttpResponseInfo& rhs) {
   was_cached = rhs.was_cached;
+  was_cache_override = rhs.was_cache_override;
   was_fetched_via_spdy = rhs.was_fetched_via_spdy;
   was_npn_negotiated = rhs.was_npn_negotiated;
   was_fetched_via_proxy = rhs.was_fetched_via_proxy;
@@ -215,6 +222,8 @@ bool HttpResponseInfo::InitFromPickle(const Pickle& pickle,
       return false;
   }
 
+  was_cache_override = (flags & RESPONSE_INFO_WAS_CACHE_OVERRIDE) != 0;
+
   was_fetched_via_spdy = (flags & RESPONSE_INFO_WAS_SPDY) != 0;
 
   was_npn_negotiated = (flags & RESPONSE_INFO_WAS_NPN) != 0;
@@ -242,6 +251,8 @@ void HttpResponseInfo::Persist(Pickle* pickle,
     flags |= RESPONSE_INFO_HAS_VARY_DATA;
   if (response_truncated)
     flags |= RESPONSE_INFO_TRUNCATED;
+  if (was_cache_override)
+    flags |= RESPONSE_INFO_WAS_CACHE_OVERRIDE;
   if (was_fetched_via_spdy)
     flags |= RESPONSE_INFO_WAS_SPDY;
   if (was_npn_negotiated) {