moc: Fix parsing of operator<

moc would skip the 'operator' keyword as unknown and try to parse a type again
but as it sees the '<' it looks for the corresponding '>' which does not exist
types can't start with '<' anyway, so return an invalid type and continue
parsing as usual

Task-number: QTBUG-36834

Change-Id: If3d27076ef9947abf8c57c594713eece9334d0b0
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@digia.com>

src/tools/moc/moc.cpp

@@ -224,6 +224,10 @@ Type Moc::parseType()
             ;
         }
         if (test(LANGLE)) {
+            if (type.name.isEmpty()) {
+                // '<' cannot start a type
+                return type;
+            }
             type.name += lexemUntil(RANGLE);
         }
         if (test(SCOPE)) {

tests/auto/tools/moc/tst_moc.cpp

@@ -128,6 +128,7 @@ public:
         emit send(value);
     }
 
+    bool operator< ( const Sender & ) const { /* QTBUG-36834 */ return true;}
 signals:
     void send(const String::Type&);
     void send(const Int::Type&);