Fix doc for Telephony Manager api and make isTtySupported public.

TelephonyManager.isTtyModeSupported is public and we are deprecating that
to use TelecomManager.isTtySupported which was system api, so making it
public.

Test: Build
Bug: 62346128
Change-Id: Idfa146b03a3c3fdb20c563c4ea0dddf2c3399da6

api/current.txt

@@ -39523,6 +39523,7 @@ package android.telecom {
     method public boolean isInManagedCall();
     method public boolean isIncomingCallPermitted(android.telecom.PhoneAccountHandle);
     method public boolean isOutgoingCallPermitted(android.telecom.PhoneAccountHandle);
+    method public boolean isTtySupported();
     method public boolean isVoiceMailNumber(android.telecom.PhoneAccountHandle, java.lang.String);
     method public void placeCall(android.net.Uri, android.os.Bundle);
     method public void registerPhoneAccount(android.telecom.PhoneAccount);

api/test-current.txt

@@ -39802,6 +39802,7 @@ package android.telecom {
     method public boolean isInManagedCall();
     method public boolean isIncomingCallPermitted(android.telecom.PhoneAccountHandle);
     method public boolean isOutgoingCallPermitted(android.telecom.PhoneAccountHandle);
+    method public boolean isTtySupported();
     method public boolean isVoiceMailNumber(android.telecom.PhoneAccountHandle, java.lang.String);
     method public void placeCall(android.net.Uri, android.os.Bundle);
     method public void registerPhoneAccount(android.telecom.PhoneAccount);

telecomm/java/android/telecom/TelecomManager.java

@@ -1345,10 +1345,8 @@ public class TelecomManager {
 
     /**
      * Returns whether TTY is supported on this device.
-     *
-     * @hide
      */
-    @SystemApi
+
     @RequiresPermission(anyOf = {
             android.Manifest.permission.READ_PRIVILEGED_PHONE_STATE,
             android.Manifest.permission.READ_PHONE_STATE

telephony/java/android/telephony/TelephonyManager.java

@@ -48,6 +48,7 @@ import android.provider.Settings.SettingNotFoundException;
 import android.service.carrier.CarrierIdentifier;
 import android.telecom.PhoneAccount;
 import android.telecom.PhoneAccountHandle;
+import android.telecom.TelecomManager;
 import android.telephony.VisualVoicemailService.VisualVoicemailTask;
 import android.telephony.ims.feature.ImsFeature;
 import android.util.Log;
@@ -5771,7 +5772,7 @@ public class TelephonyManager {
     }
 
     /**
-     * @deprecated Use {@link android.telecom.TelecomManager#silenceRinger} instead
+     * @deprecated Use {@link TelecomManager#isTtySupported()} instead
      * Whether the phone supports TTY mode.
      *
      * @return {@code true} if the device supports TTY mode, and {@code false} otherwise.