[SB] Allow carrier merged conns to inflate signal strength - Kairos

A re-implementation of If250be73b3b86ac31237d4e11327c6233bc0221f but in
the Kairos pipeline.

Bug: 423686800
Flag: com.android.systemui.status_bar_inflate_carrier_merged
Flag: com.android.systemui.status_bar_mobile_icon_kairos
Test: atest CarrierMergedConnectionRepositoryKairosAdapterTest
Test: atest CarrierMergedConnectionRepositoryKairosTest

Test: With new flag on and Kairos on:
 (adb shell am broadcast -a com.android.systemui.demo -e command
network -e wifi carriermerged -e slot 2 -e level 4 -e numlevels 5 -e
inflate false) -> verify triangle with W+ displays with 4/4 bars filled
in (numlevels=5 means the level can be in range [0-4])
 (adb shell am broadcast -a com.android.systemui.demo -e command
network -e wifi carriermerged -e slot 2 -e level 4 -e numlevels 5 -e
inflate true) -> verify triangle with W+ displays with 5/5 bars filled
in

Test: With new flag off: Verify those same test cases, but that they all
show 4/4 bars filled in

Change-Id: Ib60d22310687efe78e9e880838113cde2fde80b0