RFC: use some in-memory state in SimpleCache to quickly cache-miss some CantConditionalize cases

net/http/mock_http_cache.cc

Index: net/http/mock_http_cache.cc
diff --git a/net/http/mock_http_cache.cc b/net/http/mock_http_cache.cc
index e676122b53f4c77492d3676dac08bf517b0220dd..5b2d838d54ced895cd472c4cd17bf96564532a8e 100644
--- a/net/http/mock_http_cache.cc
+++ b/net/http/mock_http_cache.cc
@@ -68,6 +68,7 @@ struct MockDiskEntry::CallbackInfo {
 
 MockDiskEntry::MockDiskEntry(const std::string& key)
     : key_(key),
+      memory_entry_data_(0),
       doomed_(false),
       sparse_(false),
       fail_requests_(false),
@@ -521,6 +522,19 @@ size_t MockDiskCache::DumpMemoryStats(
   return 0u;
 }
 
+uint8_t MockDiskCache::GetMemoryEntryData(const std::string& key) {
+  EntryMap::iterator it = entries_.find(key);
+  if (it != entries_.end())
+    return it->second->memory_entry_data();
+  return 0;
+}
+
+void MockDiskCache::SetMemoryEntryData(const std::string& key, uint8_t data) {
+  EntryMap::iterator it = entries_.find(key);
+  if (it != entries_.end())
+    it->second->set_memory_entry_data(data);
+}
+
 void MockDiskCache::ReleaseAll() {
   EntryMap::iterator it = entries_.begin();
   for (; it != entries_.end(); ++it)