Adds TTL argument to HostCache::Set.

net/base/host_resolver_impl.cc

Index: net/base/host_resolver_impl.cc
diff --git a/net/base/host_resolver_impl.cc b/net/base/host_resolver_impl.cc
index 217f1e1329e678e0500a337fbc45cf9a33e165e1..a3b3685f742b01b16dc0f830d6081a266a6dfe79 100644
--- a/net/base/host_resolver_impl.cc
+++ b/net/base/host_resolver_impl.cc
@@ -50,6 +50,9 @@ namespace {
 // some platform's resolvers.
 const size_t kMaxHostLength = 4096;
 
+// Default TTL for successful resolutions with ProcTask.
+const unsigned kCacheEntryTTLSeconds = 60;
+
 // Helper to mutate the linked list contained by AddressList to the given
 // port. Note that in general this is dangerous since the AddressList's
 // data might be shared (and you should use AddressList::SetPort).
@@ -1353,9 +1356,14 @@ void HostResolverImpl::OnJobComplete(Job* job,
   RemoveOutstandingJob(job);
 
   // Write result to the cache.
-  if (cache_.get())
-    cache_->Set(job->key(), net_error, addrlist, base::TimeTicks::Now());
-
+  if (cache_.get()) {
+    base::TimeDelta ttl = base::TimeDelta::FromSeconds(0);
+    if (net_error == OK)
+      ttl = base::TimeDelta::FromSeconds(kCacheEntryTTLSeconds);
+    cache_->Set(job->key(), net_error, addrlist,
+                base::TimeTicks::Now(),
+                ttl);
+  }
   OnJobCompleteInternal(job, net_error, os_error, addrlist);
 }