Use scaledTouchSlop for DeviceEntryIconView

The unscaled value is taken as 8px instead of using the scaled value of 8dp, that could have resulted in touches being rejected incorrectly.

Reproducing this bug has not been easy, so not sure if this is the root cause.

Bug: 358424256
Change-Id: I91f41dece9acd1db6074aa917e10fdad4c7b3847
Test: hard to verify if this fixes the bug or not. Things seem to work  as expected.
Flag: EXEMPT bugfix