Wi-Fi Sync: Prevent crash when serializing proxy settings.

All fields are not required in manual proxy settings, and when any
optional fields were omitted it was crashing. This adds guards to only
serialized the provided fields.

Bug: 966270
Fixed: 1091405
Change-Id: I9e5aef0b6181c9e766f4779389437d2677a4fc90
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2232824Reviewed-by: James Vecore <vecore@google.com>
Commit-Queue: Jon Mann <jonmann@chromium.org>
Cr-Commit-Position: refs/heads/master@{#775759}

chromeos/components/sync_wifi/network_type_conversions.cc

@@ -146,21 +146,33 @@ ProxyConfigurationProtoFromMojo(
     sync_pb::
         WifiConfigurationSpecifics_ProxyConfiguration_ManualProxyConfiguration*
             manual_settings = proto.mutable_manual_proxy_configuration();
-    manual_settings->set_http_proxy_url(
-        proxy_settings->manual->http_proxy->host->active_value);
-    manual_settings->set_http_proxy_port(
-        proxy_settings->manual->http_proxy->port->active_value);
-    manual_settings->set_secure_http_proxy_url(
-        proxy_settings->manual->secure_http_proxy->host->active_value);
-    manual_settings->set_secure_http_proxy_port(
-        proxy_settings->manual->secure_http_proxy->port->active_value);
-    manual_settings->set_socks_host_url(
-        proxy_settings->manual->socks->host->active_value);
-    manual_settings->set_socks_host_port(
-        proxy_settings->manual->socks->port->active_value);
-    for (const std::string& domain :
-         proxy_settings->exclude_domains->active_value) {
-      manual_settings->add_whitelisted_domains(domain);
+
+    if (proxy_settings->manual->http_proxy) {
+      manual_settings->set_http_proxy_url(
+          proxy_settings->manual->http_proxy->host->active_value);
+      manual_settings->set_http_proxy_port(
+          proxy_settings->manual->http_proxy->port->active_value);
+    }
+
+    if (proxy_settings->manual->secure_http_proxy) {
+      manual_settings->set_secure_http_proxy_url(
+          proxy_settings->manual->secure_http_proxy->host->active_value);
+      manual_settings->set_secure_http_proxy_port(
+          proxy_settings->manual->secure_http_proxy->port->active_value);
+    }
+
+    if (proxy_settings->manual->socks) {
+      manual_settings->set_socks_host_url(
+          proxy_settings->manual->socks->host->active_value);
+      manual_settings->set_socks_host_port(
+          proxy_settings->manual->socks->port->active_value);
+    }
+
+    if (proxy_settings->exclude_domains) {
+      for (const std::string& domain :
+           proxy_settings->exclude_domains->active_value) {
+        manual_settings->add_whitelisted_domains(domain);
+      }
     }
   }