Cleanup options menu and licenses UI

Bug: 20503109

- Open source licenses are now displayed as a standalone Licenses
  activity.
- Show/hide result options instead of enabling/disabling them.

Change-Id: I7e1e43ac83d2417b2f59f90e6a1fc3e491c6ddc7
diff --git a/src/com/android/calculator2/Licenses.java b/src/com/android/calculator2/Licenses.java
new file mode 100644
index 0000000..053154d
--- /dev/null
+++ b/src/com/android/calculator2/Licenses.java
@@ -0,0 +1,20 @@
+package com.android.calculator2;
+
+import android.app.Activity;
+import android.os.Bundle;
+import android.webkit.WebView;
+
+public class Licenses extends Activity {
+
+    private static final String LICENSE_URL = "file:///android_asset/licenses.html";
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+
+        final WebView webView = new WebView(this);
+        webView.loadUrl(LICENSE_URL);
+
+        setContentView(webView);
+    }
+}