Handle android.R.id.home clicks in Licenses activity

Bug: 21052927
Change-Id: I4916d159f3b98966cddae0cb27468df6ea2ffd76
diff --git a/src/com/android/calculator2/Licenses.java b/src/com/android/calculator2/Licenses.java
index 053154d..4af1ea6 100644
--- a/src/com/android/calculator2/Licenses.java
+++ b/src/com/android/calculator2/Licenses.java
@@ -2,6 +2,7 @@
 
 import android.app.Activity;
 import android.os.Bundle;
+import android.view.MenuItem;
 import android.webkit.WebView;
 
 public class Licenses extends Activity {
@@ -17,4 +18,13 @@
 
         setContentView(webView);
     }
+
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+        if (item.getItemId() == android.R.id.home) {
+            onBackPressed();
+            return true;
+        }
+        return super.onOptionsItemSelected(item);
+    }
 }