Most(All?) WPF controls have bad hit detection when hosted in a System aware Win32 window inside a PMA app

Copied from internal VSO ID: 893156

Repro Steps
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1. Have .NET 4.8, and 150% primary, 100% secondary. (It should be noted that this bug seems to mostly impact high primary DPI with smaller secondary DPI. A small primary DPI with larger secondary DPI seems to behave almost perfectly, but still has some hit detection issues.)
2. Launch repro proj exe on primary
4. Move it to secondary
5. Hover over various controls

**Expected:** Hit detection works correctly for all controls in all positions

**Actual:** Hit detection gets worse as you move further away from the top/left corner of the content

**Specifically:**

1) The top/left quadrant controls should all work normally

2) The top/right quadrant should have issues when hovering on the right side controls only

3) The bottom/left quadrant should have issues when hovering on the bottom half(-ish) controls only (some of the bottom radios start to have issues too)

4) The bottom/right quadrant should have issues for all of the controls

5) All combobox dropdowns have issues but the issues do get worse the further away from top/left you get (tracked by separate VSO bug #772815)