Avoid debug messages for not implemented "grab" methods

Change-Id: Ie32b5d261854703fa17bb844cf8354709b031a4c
Reviewed-by: BogDan Vatra <bogdan@kdab.com>

src/plugins/platforms/android/qandroidplatformwindow.h

@@ -65,6 +65,9 @@ public:
     void setParent(const QPlatformWindow *window) override;
     WId winId() const override { return m_windowId; }
 
+    bool setMouseGrabEnabled(bool grab) override { return false; }
+    bool setKeyboardGrabEnabled(bool grab) override { return false; }
+
     QAndroidPlatformScreen *platformScreen() const;
 
     void propagateSizeHints() override;