Per API review, change the use of FileDescriptor to
ParcelFileDescriptor.
This change also fix nullability according to API review
feedbacks.
Fix: 126698610
Fix: 126699425
Fix: 126699232
Fix: 126700278
Test: 1. m -j
2. atest FrameworksNetTests --generate-new-metrics 50
3. m -j doc-comment-check-docs
Change-Id: I19476c50dd1ca290bf3f41973829da2bd229796a