Messaging: Language cleanup

No unnecessary boxing, enhanced for loops, redundant checks and throws,
imports (removal, reordering), possible void returns

Change-Id: I7a8e1b2007e3b0906e01b41785c518d02c2f3fab

src/com/android/messaging/ui/conversationsettings/PeopleOptionsItemView.java

@@ -19,7 +19,7 @@ package com.android.messaging.ui.conversationsettings;
 import android.content.Context;
 import android.database.Cursor;
 import androidx.appcompat.widget.SwitchCompat;
-import android.text.TextUtils;
+
 import android.util.AttributeSet;
 import android.widget.LinearLayout;
 import android.widget.TextView;