hasPhoneAccount() returns true in self managed mode, without checking if the device supports it

[wilmxre]

• Reproduced on:
• Android
• iOS

Description

I encountered a problem in self managed mode, on some Lenovo devices if you call setup like you should and you receive or start a call, you will be encountered with this error:

Remote stack trace:
	at com.android.server.telecom.TelecomServiceImpl.enforceTelecomFeature(TelecomServiceImpl.java:2449)
	at com.android.server.telecom.TelecomServiceImpl.enforcePhoneAccountModificationForPackage(TelecomServiceImpl.java:2409)
	at com.android.server.telecom.TelecomServiceImpl.-$$Nest$menforcePhoneAccountModificationForPackage(Unknown Source:0)
	at com.android.server.telecom.TelecomServiceImpl$1.registerPhoneAccount(TelecomServiceImpl.java:564)
	at com.android.internal.telecom.ITelecomService$Stub.onTransact(ITelecomService.java:857)

This usually means that a phone account couldn't register successfully or the device doesn't support this functionality.
From what i've read, calling RNCallKeep.setup() should be enough to set up your app for calls, but i tried to explicitly register a phone account, without success. I come to the conclusion that there are some devices that are simply not supporting phone account.

Now i made a workaround for devices that are encountering this specific issue and i wanted to check it programatically, but i noticed something unusual.
When calling RNCallKeep.checkPhoneAccountEnabled, this method is called:

private boolean hasPhoneAccount() {
        if (telecomManager == null) {
            this.initializeTelecomManager();
        }

        if (isSelfManaged()) {
            return true;
        }

        return isConnectionServiceAvailable() && telecomManager != null &&
            hasPermissions() && telecomManager.getPhoneAccount(handle) != null &&
            telecomManager.getPhoneAccount(handle).isEnabled();
    }

If the app is in self managed mode, this method automatically returns true, without checking if the app has a phone account.
Why is this the case? Shouldn't be better to remove that if statement and let the last return statement handle this logic? For my use case i had to remove it, i am curious what was the need for that early return.

Do self managed apps always have the possibility to register a phone account? From my experiences there are some devices, especially Lenovo tablets, where it is simply impossible to do (registerPhoneAccount not allowed on non-voice capable device).
If the config_voice_capable is simply set to false in some device, that device won't support phone accounts.

[danilvalov]

Maybe related PR: #685