Fix that debugger tooltips were overridden by editor tooltips

The debugger tells the editor if the tool tip was handled or not,
but since that information is transferred through a reference
parameter in a signal/slot connection, a second debugger engine
overrode the value of a previous one.
So never set it to 'false' so a previous 'true' is not overridden.

Fixes: QTCREATORBUG-21825
Change-Id: Iec3d15485f224ab0ad14564656886a53fec62e71
Reviewed-by: hjk <hjk@qt.io>

src/plugins/debugger/debuggertooltipmanager.cpp

@@ -1185,7 +1185,6 @@ void DebuggerToolTipManagerPrivate::slotTooltipOverrideRequested
 {
     QTC_ASSERT(handled, return);
     QTC_ASSERT(editorWidget, return);
-    *handled = false;
 
     if (!boolSetting(UseToolTipsInMainEditor))
         return;