Galaxy Nexus API 15 was unhappy to have a test theme without parent.

Set parent to android:Theme.Holo.

Test: ran tests, no more logcat warnings of:
      "You must supply a layout_height attribute."

Change-Id: I056465b2cce3dc910fc432febd3e0b6cefe9456d
diff --git a/core-ui/tests/res/values/styles.xml b/core-ui/tests/res/values/styles.xml
index ae6325b..e530e60 100644
--- a/core-ui/tests/res/values/styles.xml
+++ b/core-ui/tests/res/values/styles.xml
@@ -13,8 +13,8 @@
      See the License for the specific language governing permissions and
      limitations under the License.
 -->
-<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
-    <style name="TestActivityTheme">
+<resources>
+    <style name="TestActivityTheme" parent="android:Theme.Holo">
         <item name="android:windowAnimationStyle">@null</item>
     </style>
     <style name="TextMediumStyle" parent="@android:style/TextAppearance.Medium">