Qbs: Report command that failed

... not just its output.

Change-Id: Iecac38e5f8458bebdd609ed0a514fe361ae5bd8d
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>

src/plugins/qbsprojectmanager/qbsbuildstep.cpp

@@ -266,6 +266,10 @@ void QbsBuildStep::handleProcessResultReport(const qbs::ProcessResult &result)
         return;
 
     m_parser->setWorkingDirectory(result.workingDirectory);
+
+    QString commandline = result.binary + QLatin1Char(' ') + result.arguments.join(QLatin1String(" "));
+    addOutput(commandline, NormalOutput);
+
     foreach (const QString &line, result.stdErr) {
         m_parser->stdError(line);
         addOutput(line, ErrorOutput);