QmlDesigner.PropertyEditor: Adding lookup rules for different versions

The property editor will now try to find a pane for the specific
version first.

Example:

If we have a QtQuick.Item 2.0

We first look for: QtQuick/ItemPane_2_0.qml
And then fallback to: QtQuick/ItemPane.qml

The same does apply for the specifics file.

Task-number: QTCREATORBUG-8681
Change-Id: If210998780073295f168169d2fc424288d3bd6a0
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>

src/plugins/qmldesigner/components/propertyeditor/propertyeditor.cpp

@@ -1087,6 +1087,22 @@ QString PropertyEditor::locateQmlFile(const NodeMetaInfo &info, const QString &r
     static QDir resourcesDir(resourcePropertyEditorPath);
     QDir importDir(info.importDirectoryPath() + QLatin1String(Constants::QML_DESIGNER_SUBFOLDER));
 
+    const QString versionString = QLatin1String("_") + QString::number(info.majorVersion())
+            + QLatin1String("_")
+            + QString::number(info.minorVersion());
+
+    QString relativePathWithoutEnding = relativePath;
+    relativePathWithoutEnding.chop(4);
+    const QString relativePathWithVersion = relativePathWithoutEnding + versionString + QLatin1String(".qml");
+
+    //Check for qml files with versions first
+    if (importDir.exists(relativePathWithVersion))
+        return importDir.absoluteFilePath(relativePathWithVersion);
+    if (fileSystemDir.exists(relativePathWithVersion))
+        return fileSystemDir.absoluteFilePath(relativePathWithVersion);
+    if (resourcesDir.exists(relativePathWithVersion))
+        return resourcesDir.absoluteFilePath(relativePathWithVersion);
+
     if (importDir.exists(relativePath))
         return importDir.absoluteFilePath(relativePath);
     if (fileSystemDir.exists(relativePath))