Adds custom ttl argument to HostCache::Set.

net/dns/async_host_resolver.cc

Index: net/dns/async_host_resolver.cc
diff --git a/net/dns/async_host_resolver.cc b/net/dns/async_host_resolver.cc
index 6f6552bcfa684a7c680c9076ef19733c45e9918c..00ecf5e566e490550a977d1df78acd9da7cf7d3b 100644
--- a/net/dns/async_host_resolver.cc
+++ b/net/dns/async_host_resolver.cc
@@ -349,8 +349,9 @@ void AsyncHostResolver::OnDnsRequestComplete(
   RequestList& requests = rit->second;
   int port = requests.empty() ? 80 : requests.front()->info().port();
 
-  // Extract AddressList out of DnsResponse.
+  // Extract AddressList and TTL out of DnsResponse.
   AddressList addr_list;
+  uint32 ttl = kuint32max;
   if (result == OK) {
     IPAddressList ip_addresses;
     DnsRecordParser parser = response->Parser();
@@ -362,6 +363,7 @@ void AsyncHostResolver::OnDnsRequestComplete(
            record.rdata.size() == kIPv6AddressSize)) {
         ip_addresses.push_back(IPAddressNumber(record.rdata.begin(),
                                                record.rdata.end()));
+        ttl = std::min(ttl, record.ttl);
       }
     }
     if (!ip_addresses.empty())
@@ -389,7 +391,11 @@ void AsyncHostResolver::OnDnsRequestComplete(
     HostResolver::RequestInfo info = request->info();
     HostCache::Key key(
         info.hostname(), info.address_family(), info.host_resolver_flags());
-    cache_->Set(key, result, addr_list, base::TimeTicks::Now());
+    cache_->Set(key,
+                result,
+                addr_list,
+                base::TimeDelta::FromSeconds(ttl),
+                base::TimeTicks::Now());
   }
 
   // Cleanup requests.