Disable faking of Signal Strength indicator in the SystemUI

Lucy-L-someone

A change in 2017 introduced the ability to add 1 to the measured signal indicator (so 4 bars instead of 3 bars). This change was made directly by google in 2017 in this commit: https://android.googlesource.com/platform//frameworks/base/+/43c14d19847993aa603b781f6bc55efb273fa3fd%5E%21/#F0

And later changed by sony to be more dynamic: https://android.googlesource.com/platform//frameworks/base/+/f8c6f3483215b7a9401cb384980ccdb459f7261b%5E%21/#F2

This code is also prevelent in GrapheneOS and might be worth patching out or displaying a warning that the carrier has enabled this feature and that the signal indicator is no longer reliable for usage. The relevant code can be found here:
https://github.com/GrapheneOS/platform_frameworks_base/blob/d697c573a824058f1067fc4b317a560d71ce937c/packages/SystemUI/src/com/android/systemui/statusbar/connectivity/MobileSignalController.java#L224
Or here:
https://github.com/GrapheneOS/platform_frameworks_base/blob/16/packages/SettingsLib/src/com/android/settingslib/net/SignalStrengthUtil.java
A simple fix here might be to replace the entire method with "return false" in order to ignore any carrier config.

This change could however lead to user complains about "worse network quality" with GrapheneOS even though the measured Signal strength is the same.

I have already looked if similiar stuff got already discussed but I wasn't able to find any discussion about this particular issue, if it's duplicated, kindly link to the correct thread

I'm appreciating feedback for this and thanks for reading
(shoutout to https://nickvsnetworking.com/simple-trick-to-increase-coverage-lying-to-users-about-signal-strength/ for finding this first)

Lucy-L-someone

In case anyone is interested in checking if they are currently seeing faked signal indicators, using adb is a fast way to check:
adb shell dumpsys carrier_config | Select-String ".*inflate_signal_strength_bool.*" for windows and adb shell dumpsys carrier_config | grep "inflate_signal_strength_bool" for linux/unix.
For me the output is "inflate_signal_strength_bool = false" (2x), any amount of inflate_signal_strength_bool = true would indicate you carrier is using this "feature" to display a better indicator