IabHelper: Reason of cancelling the buy flow is lost.

STEPS TO REPRODUCE:
1. Try buying an already owned item.
2. User sees the "Item already owned message."
3. Handle activityResult doesn't distinguish this case from a "normal" 
cancellation event.

EXPECTED OUTPUT:
IabHelper.java:509 should be
result = new IabResult(responseCode, "User canceled.");

ACTUAL OUTPUT:
IabHelper.java:509 is
result = new IabResult(IABHELPER_USER_CANCELLED, "User canceled.");

AFFECTED ORDER IDS (IF RELEVANT):
n/a
OS VERSION:
n/a
MARKET/MYAPPS VERSION:
n/a
DEVICE:
n/a
OUTPUT FROM ADB BUGREPORT ATTACHED:
n/a

NOTES:

IabHelper revision: 
https://code.google.com/p/marketbilling/source/browse/v3/src/com/example/android
/trivialdrivesample/util/IabHelper.java?spec=svn7ec85a9b619fc5f85023bc8125e7e6b1
ab4dd69f&r=7ec85a9b619fc5f85023bc8125e7e6b1ab4dd69f

Original issue reported on code.google.com by adrian.r...@gmail.com on 10 Jun 2013 at 12:54

patreek / marketbilling

IabHelper: Reason of cancelling the buy flow is lost. #126