Migrate system dialer config to RoleManager

Test: adb logcat | grep Telecomm  - to ensure correct default dialer detected
go to settings-default apps and ensure correct dialer selected in UI
Change-Id: Ib34c07b8259875dfb3c8ea848410436cbeec3796

core/java/android/text/TextUtils.java

@@ -2182,6 +2182,13 @@ public class TextUtils {
         return Character.isWhitespace(codePoint) || codePoint == NBSP_CODE_POINT;
     }
 
+    /** @hide */
+    @Nullable
+    public static String withoutPrefix(@Nullable String prefix, @Nullable String str) {
+        if (prefix == null || str == null) return str;
+        return str.startsWith(prefix) ? str.substring(prefix.length()) : str;
+    }
+
     /**
      * Remove html, remove bad characters, and truncate string.
      *

core/java/com/android/internal/util/ArrayUtils.java

@@ -690,4 +690,17 @@ public class ArrayUtils {
         }
         return result;
     }
+
+    /**
+     * Returns the first element from the array for which
+     * condition {@code predicate} is true, or null if there is no such element
+     */
+    public static @Nullable <T> T find(@Nullable T[] items,
+            @NonNull java.util.function.Predicate<T> predicate) {
+        if (isEmpty(items)) return null;
+        for (final T item : items) {
+            if (predicate.test(item)) return item;
+        }
+        return null;
+    }
 }

core/res/res/values/config.xml

@@ -1936,6 +1936,7 @@
          holders, with each item in the format of "ROLE_NAME: PACKAGE_NAME_1, PACKAGE_NAME_2". -->
     <string-array name="config_defaultRoleHolders" translatable="false">
         <item>android.app.role.SMS: com.android.messaging</item>
+        <item>android.app.role.DIALER: com.android.phone</item>
     </string-array>
 
     <!-- Enable/disable default bluetooth profiles: