Update theme of ActivityPicker

Bug: 7971340
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index bdf8296..78b16bb 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -1201,7 +1201,7 @@
 
         <activity android:name="ActivityPicker"
                 android:label="@string/activity_picker_label"
-                android:theme="@*android:style/Theme.Dialog.Alert"
+                android:theme="@*android:style/Theme.Holo.Dialog.Alert"
                 android:finishOnCloseSystemDialogs="true">
             <intent-filter>
                 <action android:name="android.intent.action.PICK_ACTIVITY" />