Prevent modification of TTY setting while in video call or conf call.

Prevent the TTY mode from being changed while the device is in a video
call, downgraded video call, or a conference call.

Test: Manual testing.
Bug: 28512893
Change-Id: If7dfced29b6fb4503b73fdd3786ddcbbf8d9f788
diff --git a/src/com/android/phone/settings/AccessibilitySettingsFragment.java b/src/com/android/phone/settings/AccessibilitySettingsFragment.java
index ea19f75..0c186a9 100644
--- a/src/com/android/phone/settings/AccessibilitySettingsFragment.java
+++ b/src/com/android/phone/settings/AccessibilitySettingsFragment.java
@@ -24,7 +24,6 @@
 import android.preference.PreferenceFragment;
 import android.preference.PreferenceScreen;
 import android.provider.Settings;
-import android.telecom.TelecomManager;
 import android.telephony.CarrierConfigManager;
 import android.telephony.PhoneStateListener;
 import android.telephony.TelephonyManager;
@@ -35,9 +34,6 @@
 import com.android.internal.telephony.PhoneFactory;
 import com.android.phone.PhoneGlobals;
 import com.android.phone.R;
-import com.android.phone.settings.TtyModeListPreference;
-
-import java.util.List;
 
 public class AccessibilitySettingsFragment extends PreferenceFragment {
     private static final String LOG_TAG = AccessibilitySettingsFragment.class.getSimpleName();
@@ -60,7 +56,7 @@
             if (pref != null) {
                 final boolean isVolteTtySupported = ImsManager.isVolteEnabledByPlatform(mContext)
                         && getVolteTtySupported();
-                pref.setEnabled((isVolteTtySupported && !isVideoCallInProgress()) ||
+                pref.setEnabled((isVolteTtySupported && !isVideoCallOrConferenceInProgress()) ||
                         (state == TelephonyManager.CALL_STATE_IDLE));
             }
         }
@@ -144,15 +140,15 @@
                 CarrierConfigManager.KEY_CARRIER_VOLTE_TTY_SUPPORTED_BOOL);
     }
 
-    private boolean isVideoCallInProgress() {
+    private boolean isVideoCallOrConferenceInProgress() {
         final Phone[] phones = PhoneFactory.getPhones();
         if (phones == null) {
-            if (DBG) Log.d(LOG_TAG, "isVideoCallInProgress: No phones found. Return false");
+            if (DBG) Log.d(LOG_TAG, "isVideoCallOrConferenceInProgress: No phones found.");
             return false;
         }
 
         for (Phone phone : phones) {
-            if (phone.isVideoCallPresent()) {
+            if (phone.isImsVideoCallOrConferencePresent()) {
                 return true;
             }
         }