[android] - replace platform default implementation using nunicode for uppercasing an lowercasing with an Android specific String.java equivalent

platform/android/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/string/UppperLowerCaseTest.java

@@ -0,0 +1,50 @@
+package com.mapbox.mapboxsdk.testapp.string;
+
+import com.mapbox.mapboxsdk.testapp.activity.BaseActivityTest;
+import com.mapbox.mapboxsdk.testapp.activity.espresso.EspressoTestActivity;
+import org.junit.Test;
+
+import static junit.framework.Assert.assertEquals;
+
+/**
+ * Test verifying if String#toUpperCase and String#toLowerCase produces desired results
+ * <p>
+ * See core test in https://github.com/mapbox/mapbox-gl-native/blob/master/test/util/text_conversions.test.cpp
+ * </p>
+ */
+public class UppperLowerCaseTest extends BaseActivityTest {
+
+  @Override
+  protected Class getActivityClass() {
+    return EspressoTestActivity.class;
+  }
+
+  @Test
+  public void testToUpperCase() {
+    assertEquals("STREET", "strEEt".toUpperCase());  // EN
+    assertEquals("ROAD", "rOAd".toUpperCase());      // EN
+
+    assertEquals("STRASSE", "straße".toUpperCase()); // DE
+    assertEquals("MASSE", "maße".toUpperCase());     // DE
+    assertEquals("WEISSKOPFSEEADLER", "weißkopfseeadler".toUpperCase()); // DE
+
+    assertEquals("BÊNÇÃO", "bênção".toUpperCase()); // PT
+    assertEquals("AZƏRBAYCAN", "Azərbaycan".toUpperCase()); // AZ
+    assertEquals("ὈΔΥΣΣΕΎΣ", "Ὀδυσσεύς".toUpperCase()); // GR
+  }
+
+  @Test
+  public void testToLowerCase() {
+    assertEquals("street", "strEEt".toLowerCase());  // EN
+    assertEquals("road", "rOAd".toLowerCase());      // EN
+
+    assertEquals("straße", "Straße".toLowerCase());   // DE
+    assertEquals("strasse", "STRASSE".toLowerCase()); // DE
+    assertEquals("masse", "MASSE".toLowerCase());     // DE
+    assertEquals("weisskopfseeadler", "weiSSkopfseeadler".toLowerCase()); // DE
+
+    assertEquals("bênção", "BÊNÇÃO".toLowerCase()); // PT
+    assertEquals("azərbaycan", "AZƏRBAYCAN".toLowerCase()); //
+  }
+
+}