DeviceProcessDialog: Introduce methods for modal/non-modal use.

Add methods to be able to use the dialog as a non-modal
dialog showing a list of processes or a modal-dialog
for selecting a process.

Connect double-click to 'Accept' for the modal
case (regression from 2.5).

Change-Id: If05a1c40ee6a41135d943e9919a1250db03eeffb
Reviewed-by: hjk <qthjk@ovi.com>

src/plugins/debugger/debuggerplugin.cpp

@@ -1560,6 +1560,7 @@ void DebuggerPluginPrivate::attachToRunningApplication()
 void DebuggerPluginPrivate::attachToProcess(bool startServerOnly)
 {
     DeviceProcessesDialog *dlg = new DeviceProcessesDialog(mainWindow());
+    dlg->addAcceptButton(DeviceProcessesDialog::tr("&Attach to Process"));
     dlg->showAllDevices();
     if (dlg->exec() == QDialog::Rejected) {
         delete dlg;