Bug 892939: Remove PrepareAdapterTask, r=echou,gyeh

PrepareAdapterRunnable does not block for DBus anymore, so the
intermediate step of PrepareAdapterTask in the main thread is
unnecessary. This patch merges the code of PrepareAdapterTask
into PrepareAdapterRunnable and removes PrepareAdapterTask.
PrepareAdapterRunnable now runs directly on the main thread.

dom/bluetooth/linux/BluetoothDBusService.cpp

@@ -1258,6 +1258,10 @@ private:
 class PrepareAdapterRunnable : public nsRunnable
 {
 public:
+  PrepareAdapterRunnable(const nsAString& aAdapterPath)
+    : mAdapterPath(aAdapterPath)
+  { }
+
   NS_IMETHOD Run()
   {
     static const dbus_uint32_t sServices[] = {
@@ -1266,14 +1270,23 @@ public:
       BluetoothServiceClass::OBJECT_PUSH
     };
 
-    MOZ_ASSERT(!NS_IsMainThread());
+    MOZ_ASSERT(NS_IsMainThread());
 
-    nsRefPtr<DBusReplyHandler> handler = new AddReservedServiceRecordsReplyHandler();
-    MOZ_ASSERT(handler.get());
+    nsRefPtr<RawDBusConnection> threadConnection = gThreadConnection;
+
+    if (!threadConnection.get()) {
+      BT_WARNING("%s: DBus connection has been closed.", __FUNCTION__);
+      return false;
+    }
+
+    sAdapterPath = mAdapterPath;
+
+    nsRefPtr<DBusReplyHandler> handler =
+      new AddReservedServiceRecordsReplyHandler();
 
     const dbus_uint32_t* services = sServices;
 
-    bool success = dbus_func_args_async(gThreadConnection->GetConnection(), -1,
+    bool success = dbus_func_args_async(threadConnection->GetConnection(), -1,
                                         DBusReplyHandler::Callback, handler.get(),
                                         NS_ConvertUTF16toUTF8(sAdapterPath).get(),
                                         DBUS_ADAPTER_IFACE, "AddReservedServiceRecords",
@@ -1286,30 +1299,9 @@ public:
 
     return NS_OK;
   }
-};
-
-class PrepareAdapterTask : public nsRunnable
-{
-public:
-  PrepareAdapterTask(const nsAString& aPath)
-    : mPath(aPath)
-  {
-  }
-
-  nsresult Run()
-  {
-    MOZ_ASSERT(NS_IsMainThread());
-
-    BluetoothService* bs = BluetoothService::Get();
-    NS_ENSURE_TRUE(bs, NS_ERROR_FAILURE);
-    sAdapterPath = mPath;
-    nsRefPtr<nsRunnable> func(new PrepareAdapterRunnable());
-    bs->DispatchToCommandThread(func);
-    return NS_OK;
-  }
 
 private:
-  nsString mPath;
+  nsString mAdapterPath;
 };
 
 class SendPlayStatusTask : public nsRunnable
@@ -1517,7 +1509,7 @@ EventFilter(DBusConnection* aConn, DBusMessage* aMsg, void* aData)
       errorStr.AssignLiteral("Cannot parse manager path!");
     } else {
       v = NS_ConvertUTF8toUTF16(str);
-      NS_DispatchToMainThread(new PrepareAdapterTask(v.get_nsString()));
+      NS_DispatchToMainThread(new PrepareAdapterRunnable(v.get_nsString()));
     }
   } else if (dbus_message_is_signal(aMsg, DBUS_MANAGER_IFACE,
                                     "PropertyChanged")) {
@@ -1671,10 +1663,10 @@ BluetoothDBusService::StartInternal()
   nsAutoString replyError;
   if (!GetDefaultAdapterPath(v, replyError)) {
     // Adapter path is not ready yet
-    // Let's do PrepareAdapterTask when we receive signal 'AdapterAdded'
+    // Let's do PrepareAdapterRunnable when we receive signal 'AdapterAdded'
   } else {
-    // Adapter path has been ready. let's do PrepareAdapterTask now
-    nsRefPtr<PrepareAdapterTask> b = new PrepareAdapterTask(v.get_nsString());
+    // Adapter path has been ready. let's do PrepareAdapterRunnable now
+    nsRefPtr<PrepareAdapterRunnable> b = new PrepareAdapterRunnable(v.get_nsString());
     if (NS_FAILED(NS_DispatchToMainThread(b))) {
       NS_WARNING("Failed to dispatch to main thread!");
     }