ExtensionSystem: Always generate profiling data

The overhead is minimal and can be shown at a later point even
when not printing profiling data to the terminal.
Move the data to the plugin spec for later retrieval.

Task-number: QTCREATORBUG-29540
Change-Id: I392ff85a8a8b5c01ecba07fefd06e5029f692bf6
Reviewed-by: Cristian Adam <cristian.adam@qt.io>
Reviewed-by: hjk <hjk@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

src/libs/extensionsystem/pluginspec.cpp

@@ -402,6 +402,11 @@ QJsonObject PluginSpec::metaData() const
     return d->metaData;
 }
 
+const PerformanceData &PluginSpec::performanceData() const
+{
+    return d->performanceData;
+}
+
 /*!
     Returns a list of descriptions of command line arguments the plugin processes.
 */