Update from https://crrev.com/307330

net/http/disk_cache_based_quic_server_info.cc

Index: net/http/disk_cache_based_quic_server_info.cc
diff --git a/net/http/disk_cache_based_quic_server_info.cc b/net/http/disk_cache_based_quic_server_info.cc
index fd3a6fa5dff4d945a1fd9132da8ad94fe3fe4b4c..6a5ee175d5187f8773a75d2c88f8dc26415e26f5 100644
--- a/net/http/disk_cache_based_quic_server_info.cc
+++ b/net/http/disk_cache_based_quic_server_info.cc
@@ -200,12 +200,18 @@ void DiskCacheBasedQuicServerInfo::OnIOComplete(CacheOperationDataShim* unused,
   rv = DoLoop(rv);
   if (rv == ERR_IO_PENDING)
     return;
+
+  base::WeakPtr<DiskCacheBasedQuicServerInfo> weak_this =
+      weak_factory_.GetWeakPtr();
+
   if (!wait_for_ready_callback_.is_null()) {
     wait_for_data_end_time_ = base::TimeTicks::Now();
     RecordLastFailure();
     base::ResetAndReturn(&wait_for_ready_callback_).Run(rv);
   }
-  if (ready_ && !pending_write_data_.empty()) {
+  // |wait_for_ready_callback_| could delete the object if there is an error.
+  // Check if |weak_this| still exists before accessing it.
+  if (weak_this.get() && ready_ && !pending_write_data_.empty()) {
     DCHECK_EQ(NONE, state_);
     PersistInternal();
   }