This converts the Shill clients to allow propagation of shill errors

chromeos/dbus/shill_client_helper.cc

Index: chromeos/dbus/shill_client_helper.cc
diff --git a/chromeos/dbus/shill_client_helper.cc b/chromeos/dbus/shill_client_helper.cc
index bd421bcfa453f26f02bd5b809d0dc0f2038d275a..6b68784a28ea43675e62989f5a2fb5fa91f68784 100644
--- a/chromeos/dbus/shill_client_helper.cc
+++ b/chromeos/dbus/shill_client_helper.cc
@@ -14,7 +14,7 @@
 namespace chromeos {
 
 ShillClientHelper::ShillClientHelper(dbus::Bus* bus,
-                                           dbus::ObjectProxy* proxy)
+                                     dbus::ObjectProxy* proxy)
     : blocking_method_caller_(bus, proxy),
       proxy_(proxy),
       weak_ptr_factory_(this) {
@@ -23,13 +23,14 @@ ShillClientHelper::ShillClientHelper(dbus::Bus* bus,
 ShillClientHelper::~ShillClientHelper() {
 }
 
-void ShillClientHelper::SetPropertyChangedHandler(
-    const PropertyChangedHandler& handler) {
-  property_changed_handler_ = handler;
+void ShillClientHelper::AddPropertyChangedObserver(
+    PropertyChangedObserver* obs) {

[hashimoto, 2012/09/21 11:52:01]

Rename this to |observer|

[Greg Spencer (Chromium), 2012/09/21 22:03:47]

Done.

+  observer_list_.AddObserver(obs);
 }
 
-void ShillClientHelper::ResetPropertyChangedHandler() {
-  property_changed_handler_.Reset();
+void ShillClientHelper::RemovePropertyChangedObserver(
+    PropertyChangedObserver* obs) {

[hashimoto, 2012/09/21 11:52:01]

ditto.

[Greg Spencer (Chromium), 2012/09/21 22:03:47]

Done.

+  observer_list_.RemoveObserver(obs);
 }
 
 void ShillClientHelper::MonitorPropertyChanged(
@@ -62,6 +63,21 @@ void ShillClientHelper::CallObjectPathMethod(
                                 callback));
 }
 
+void ShillClientHelper::CallObjectPathMethodWithErrorCallback(
+    dbus::MethodCall* method_call,
+    const ObjectPathDBusMethodCallback& callback,
+    const ErrorCallback& error_callback) {
+  proxy_->CallMethodWithErrorCallback(
+      method_call,
+      dbus::ObjectProxy::TIMEOUT_USE_DEFAULT,
+      base::Bind(&ShillClientHelper::OnObjectPathMethod,
+                 weak_ptr_factory_.GetWeakPtr(),
+                 callback),
+      base::Bind(&ShillClientHelper::OnError,
+                 weak_ptr_factory_.GetWeakPtr(),
+                 error_callback));
+}
+
 void ShillClientHelper::CallDictionaryValueMethod(
     dbus::MethodCall* method_call,
     const DictionaryValueCallback& callback) {
@@ -144,7 +160,7 @@ base::DictionaryValue* ShillClientHelper::CallDictionaryValueMethodAndBlock(
 
 // static
 void ShillClientHelper::AppendValueDataAsVariant(dbus::MessageWriter* writer,
-                                                    const base::Value& value) {
+                                                 const base::Value& value) {
   // Support basic types and string-to-string dictionary.
   switch (value.GetType()) {
     case base::Value::TYPE_DICTIONARY: {
@@ -185,14 +201,14 @@ void ShillClientHelper::AppendValueDataAsVariant(dbus::MessageWriter* writer,
 }
 
 void ShillClientHelper::OnSignalConnected(const std::string& interface,
-                                             const std::string& signal,
-                                             bool success) {
+                                          const std::string& signal,
+                                          bool success) {
   LOG_IF(ERROR, !success) << "Connect to " << interface << " " << signal
                           << " failed.";
 }
 
 void ShillClientHelper::OnPropertyChanged(dbus::Signal* signal) {
-  if (property_changed_handler_.is_null())
+  if (!observer_list_.might_have_observers())

[hashimoto, 2012/09/21 11:52:01]

This early exit was necessary since calling Run() against NULL callback results
in SIGSEGV.
With observer list, we no longer have to check this.

[Greg Spencer (Chromium), 2012/09/21 22:03:47]

Sure, but why not early exit anyhow, to avoid having to create the reader and
pop the values?

     return;
 
   dbus::MessageReader reader(signal);
@@ -202,11 +218,14 @@ void ShillClientHelper::OnPropertyChanged(dbus::Signal* signal) {
   scoped_ptr<base::Value> value(dbus::PopDataAsValue(&reader));
   if (!value.get())
     return;
-  property_changed_handler_.Run(name, *value);
+
+  FOR_EACH_OBSERVER(PropertyChangedObserver, observer_list_,
+                    OnPropertyChanged(name, *value));
+
 }
 
 void ShillClientHelper::OnVoidMethod(const VoidDBusMethodCallback& callback,
-                                        dbus::Response* response) {
+                                     dbus::Response* response) {
   if (!response) {
     callback.Run(DBUS_METHOD_CALL_FAILURE);
     return;
@@ -272,7 +291,7 @@ void ShillClientHelper::OnDictionaryValueMethodWithErrorCallback(
 }
 
 void ShillClientHelper::OnError(const ErrorCallback& error_callback,
-                                   dbus::ErrorResponse* response) {
+                                dbus::ErrorResponse* response) {
   std::string error_name;
   std::string error_message;
   if (response) {