DebuggingHelpers: Update after built for newly added versions

One can already build debugging helpers for Qt Versions not yet
registered to QtVersionManager - which resulted in a QTC_ASSERT
+ the changes after the built were not picked up.

Change-Id: I12a769df6e18a05b0d1677fd913f4064efed3429
Reviewed-on: http://codereview.qt.nokia.com/2168
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Daniel Teske <daniel.teske@nokia.com>

src/plugins/qtsupport/qtversionmanager.cpp

@@ -498,13 +498,8 @@ void QtVersionManager::updateDocumentation()
     helpManager->registerDocumentation(files);
 }
 
-void QtVersionManager::updateQtVersion(int id)
+void QtVersionManager::updateDumpFor(const QString &qmakeCommand)
 {
-    BaseQtVersion *qtVersion = version(id);
-    QTC_ASSERT(qtVersion, return);
-
-    // update actually all Qt versions with the same qmake command
-    const QString qmakeCommand = qtVersion->qmakeCommand();
     foreach (BaseQtVersion *v, versions()) {
         if (v->qmakeCommand() == qmakeCommand)
             v->recheckDumper();