TextEditor: add text cursor to assist interface

This will allow us to request assistance for a specific selection
instead of just the position.

Change-Id: Ib8e5b32d4a8f2936e5a6f1b7ac968d7f1d8d9de6
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/qmljseditor/qmljscompletionassist.h

@@ -105,8 +105,7 @@ private:
 class QMLJSEDITOR_EXPORT QmlJSCompletionAssistInterface : public TextEditor::AssistInterface
 {
 public:
-    QmlJSCompletionAssistInterface(QTextDocument *textDocument,
-                                   int position,
+    QmlJSCompletionAssistInterface(const QTextCursor &cursor,
                                    const Utils::FilePath &fileName,
                                    TextEditor::AssistReason reason,
                                    const QmlJSTools::SemanticInfo &info);