Domain Reliability: Don't crash on shutdown with uploads pending

components/domain_reliability/monitor.cc

Index: components/domain_reliability/monitor.cc
diff --git a/components/domain_reliability/monitor.cc b/components/domain_reliability/monitor.cc
index 2da1d509dd17718e182f26708671c3a276199ec4..2ebc9d406bfcf5b76e1e9791c311177a58274b25 100644
--- a/components/domain_reliability/monitor.cc
+++ b/components/domain_reliability/monitor.cc
@@ -120,6 +120,8 @@ DomainReliabilityMonitor::~DomainReliabilityMonitor() {
     DCHECK(OnPrefThread());
 
   net::NetworkChangeNotifier::RemoveNetworkChangeObserver(this);
+
+  DCHECK(!uploader_);
 }
 
 void DomainReliabilityMonitor::MoveToNetworkThread() {
@@ -155,6 +157,10 @@ void DomainReliabilityMonitor::InitURLRequestContext(
                                                 url_request_context_getter);
 }
 
+void DomainReliabilityMonitor::Shutdown() {
+  uploader_.reset();

[mmenke, 2016/09/26 21:30:09]

I don't see any checks for a null uploader anywhere?  Can deleting a URLRequest
cause DomainReliabilityMonitor to tell uploader_ to start a new URLRequest?

[Julia Tuttle, 2016/09/27 16:49:59]

Not sure, but fixed with new Shutdown.

+}
+
 void DomainReliabilityMonitor::AddBakedInConfigs() {
   DCHECK(OnNetworkThread());
   DCHECK(moved_to_network_thread_);