Trigger data reduction proxy unreachable message via on proxy fall back.

chrome/browser/net/chrome_network_delegate.cc

Index: chrome/browser/net/chrome_network_delegate.cc
diff --git a/chrome/browser/net/chrome_network_delegate.cc b/chrome/browser/net/chrome_network_delegate.cc
index 77abac00de1b6e2699cf068e2e6d57f191d015f6..11dce54a4fcffb7a6312b711c8150e2a549bced2 100644
--- a/chrome/browser/net/chrome_network_delegate.cc
+++ b/chrome/browser/net/chrome_network_delegate.cc
@@ -444,7 +444,7 @@ void ChromeNetworkDelegate::OnResolveProxy(
 void ChromeNetworkDelegate::OnProxyFallback(const net::ProxyServer& bad_proxy,
                                             int net_error) {
   if (data_reduction_proxy_usage_stats_) {
-    data_reduction_proxy_usage_stats_->RecordBypassEventHistograms(
+    data_reduction_proxy_usage_stats_->OnProxyFallback(
         bad_proxy, net_error);
   }
 }