Fix a crash in PhysicalKeyboardFragment

The crash is caused by using getContext() in a background thread. This CL changes it to use the context passed in as a parameter.

Bug: 373789342
Change-Id: Ia0197640b3d01cf305bfd9ebc8465b0c8e0dc016
Test: manual and presubmit
Flag: EXEMPT bugfix
1 file changed