Add custom automation peer for various controls

[batzen]

The following controls should provide a custom automation peer:

• [x] Button
• [x] DropDownButton
• [x] SplitButton
• [x] CheckBox
• [x] InRibbonGallery
• [x] ScreenTip
• [x] Backstage
• [ ] BackstageTabControl
• [ ] BackstageTabItem
• [ ] StartScreen
• [x] ComboBox
• [x] Ribbon
• [x] RibbonGroupBox
• [x] RibbonTabControl
• [x] RibbonTabItem
• [x] RadioButton
• [ ] Spinner
• [x] TextBox
• [x] ToggleButton
• [x] TwoLineLabel

[batzen]

#768 for reference

[dipts]

I'm using UIAutomation for regression testing, for this I need access to the toggle state of a ToggleButton. With version 7.1 there is no Button-Interface with TogglePattern anymore. The only interface exposed to UIA is the DataItem with an Image.

I don't know the correct way, if there should be a Button beside the Image below the DataItem, or if DataItem should expose a TogglePattern.

[batzen]

That's of course not the intended behavior. I am also no expert in writing automation peers, but as there was no feedback during the preview versions I thought everything was fine. Will have a look at this right now.

[batzen]

@dipts should be fixed in the latest CI-build

[dipts]

@batzen Works perfectly now. Thank you very much!

[batzen]

If you find any more issues please report them. As I don't have any disabilities and don't rely on automation peers for ui tests (wrote my own custom framework) it's quite difficult to get everything right.