Add documentation for ExtensionSystem::invoke

Task-number: QTCREATORBUG-23544
Change-Id: I41078ef167f1dd1592cf22a69d0cad13429db201
Reviewed-by: Eike Ziller <eike.ziller@qt.io>
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>

src/libs/extensionsystem/invoker.cpp

@@ -27,6 +27,45 @@
 
 namespace ExtensionSystem {
 
+/*!
+    \class ExtensionSystem::InvokerBase
+    \internal
+*/
+
+/*!
+    \class ExtensionSystem::Invoker
+    \internal
+*/
+
+/*!
+    \fn Result invoke(QObject *target, const char *slot)
+    Invokes \a slot on \a target by name via Qt's meta method system.
+
+    Returns the result of the meta call.
+*/
+
+/*!
+    \fn Result invoke(QObject *target, const char *slot, const T0 &t0)
+    Invokes \a slot on \a target with argument \a t0 by name via Qt's meta method system.
+
+    Returns the result of the meta call.
+*/
+
+/*!
+    \fn Result invoke(QObject *target, const char *slot, const T0 &t0, const T1 &t1)
+    Invokes \a slot on \a target with arguments \a t0 and \a t1 by name via Qt's meta method system.
+
+    Returns the result of the meta call.
+*/
+
+/*!
+    \fn Result invoke(QObject *target, const char *slot, const T0 &t0, const T1 &t1, const T2 &t2)
+    Invokes \a slot on \a target with arguments \a t0, \a t1 and \a t2 by name
+    via Qt's meta method system.
+
+    Returns the result of the meta call.
+*/
+
 InvokerBase::InvokerBase()
 {
     lastArg = 0;

src/libs/extensionsystem/invoker.h

@@ -150,6 +150,7 @@ public:
     }
 };
 
+#ifndef Q_QDOC
 template <class Result>
 Result invokeHelper(InvokerBase &in, QObject *target, const char *slot)
 {
@@ -164,6 +165,7 @@ inline void invokeHelper<void>(InvokerBase &in, QObject *target, const char *slo
 {
     in.invoke(target, slot);
 }
+#endif
 
 template<class Result>
 Result invoke(QObject *target, const char *slot)