Moving come tests to Roboelectric

> Fixing resource loading in robo tests

Change-Id: Id5b8a0e4916a2a200da7a41b03f19846834beb1f

robolectric_tests/src/com/android/launcher3/util/IntSetTest.java

@@ -21,7 +21,6 @@ import org.junit.Test;
 import org.junit.runner.RunWith;
 
 import org.robolectric.RobolectricTestRunner;
-import org.robolectric.annotation.Config;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
@@ -31,7 +30,6 @@ import static org.junit.Assert.assertTrue;
  * Robolectric unit tests for {@link IntSet}
  */
 @RunWith(RobolectricTestRunner.class)
-@Config(sdk = 26)
 public class IntSetTest {
 
     @Test