CMake: Emit errorOccurred on errors in server-mode

Change-Id: I0dd262ccaad3704c70dedff5e0b102032c46d2df
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/plugins/cmakeprojectmanager/servermodereader.cpp

@@ -385,6 +385,7 @@ void ServerModeReader::handleError(const QString &message)
     TaskHub::addTask(Task::Error, message, ProjectExplorer::Constants::TASK_CATEGORY_BUILDSYSTEM,
                      Utils::FileName(), -1);
     stop();
+    emit errorOccured(message);
 }
 
 void ServerModeReader::handleProgress(int min, int cur, int max, const QString &inReplyTo)