docs: Fixed code snippet for unbinding from IAB v3 service.
Bug: 11858905

Change-Id: Id1af4fc50a020ab520b2c836df8182db6c3a35bd
diff --git a/docs/html/google/play/billing/billing_integrate.jd b/docs/html/google/play/billing/billing_integrate.jd
index 57227a8..949752a 100644
--- a/docs/html/google/play/billing/billing_integrate.jd
+++ b/docs/html/google/play/billing/billing_integrate.jd
@@ -157,7 +157,7 @@
 @Override
 public void onDestroy() {
     super.onDestroy();
-    if (mServiceConn != null) {
+    if (mService != null) {
         unbindService(mServiceConn);
     }	
 }