Backport PR
#2901: Fix inputhook_wx on osx...
Backport PR
#2901: Fix inputhook_wx on osx
Use the inputhook_wx2 implementation on osx, fixing
#2762.
Please review. Perhaps it would be better to test with `'cocoa' in wx.version()`, write a new implementation without the Pending/Dispatch loop, or just use inputhook_wx2 on all platforms.