In darwin/arm64, with Xcode13 toolchain, the nm shows a prefix `_` in
the import path, which was previously not handled.
Such as:
000000010009cd70 t _golang.org/x/mobile/app.(*app).Events
000000010009ce70 t _golang.org/x/mobile/app.(*app).Filter
000000010009cdf0 t _golang.org/x/mobile/app.(*app).Publish
000000010009cd80 t _golang.org/x/mobile/app.(*app).Send
000000010009d870 t _golang.org/x/mobile/app.(*app).loop
000000010009d7f0 t _golang.org/x/mobile/app.(*app).loop.func1
This change fixes the regexp for import package extraction and permits
TestRegexImportGolangXPackage to pass.
Change-Id: I5f8b02177c8b022283276f2ddffaa8bb277aa255
Reviewed-on: https://go-review.googlesource.com/c/mobile/+/346154
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Hajime Hoshi <hajimehoshi@gmail.com>
Trust: Dmitri Shuralyov <dmitshur@golang.org>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
f7a629369e