Updating sample plugin to test java class loading.

samples/BrowserPlugin/src/com/android/sampleplugin/BackgroundTest.java

@@ -0,0 +1,11 @@
+package com.android.sampleplugin;
+
+public class BackgroundTest {
+
+    public BackgroundTest() {}
+    
+    public int addInt(int x, int y) {
+        return x + y;
+    }
+    
+}