Make the linenumbers area 5 digits big

That's enough for everyone.
Task-Nr: QTCREATORBUG-5056

Change-Id: Ib35b7d55a571a6d68ffa91ffa2cdb4666a22b9b8
Reviewed-on: http://codereview.qt.nokia.com/301

Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Daniel Teske <daniel.teske@nokia.com>

src/plugins/projectexplorer/taskwindow.cpp

@@ -519,7 +519,7 @@ int TaskModel::sizeOfLineNumber(const QFont &font)
     if (m_sizeOfLineNumber == 0 || fontKey != m_lineMeasurementFont) {
         QFontMetrics fm(font);
         m_lineMeasurementFont = fontKey;
-        m_sizeOfLineNumber = fm.width("8888");
+        m_sizeOfLineNumber = fm.width("88888");
     }
     return m_sizeOfLineNumber;
 }