Improve triggering of touch event and introduce Eraser device

[skarllot]

Description of Changes

• Capture touch pressure for Mac, UWP and iOS.
• Capture wheel delta for Mac.
• Support touch and stylus on WPF platform.
• Support mouse on Android platform.
• Introduce Eraser device.
• Add a TO-DO for Tizen where device ID is buggy.

API Changes

Added:

• Eraser member for SKTouchDeviceType enum.
• Constructor .ctor(long, SKTouchAction, SKPoint, bool, float) for SKTouchEventArgs class.

Behavioral Changes

• Android triggers Pressed, Up and Cancel events for all pointers instead of triggering just for Moved event.
• When Stylus pen is inverted trigger touch event as Eraser device.

PR Checklist

• Has tests (if omitted, state reason in description)
• Rebased on top of master at time of PR
• Changes adhere to coding standard
• Updated documentation

[msftclas]

All CLA requirements met.

[mattleibow]

Thanks for this PR. Sorry it took so long to get to it.

[skarllot]

Should I close this PR? After 2 years I think that it will not be merged anymore

[nshtinkov]

Is this still planned? It would fix #1814 and the Eraser addition is also quite needed.

Being able to detect pen pressure on Windows is essential, and it is a one-line fix. If this pull request is not getting further attention, I can make a new one that will fix at least the pressure issue.

[mattleibow]

/rebase

[nshtinkov]

Line 133 should be ?? 1 because 1 is the default pressure for SKTouchEventArgs. Also this change would fix the compiler error.
pr1239fix.patch

[nshtinkov]

As in my comment above, the attached one-line patch is required to fix the build and ensure that pressure handling is consistent across platforms and devices (i.e. use a default value of 1).
pr1239fix.patch