Don't try to decode JSON request data if the request content length is null

Change-Id: I8a1485d4e28f6710c7fc68c2a6b755331aa35a7c
(cherry picked from commit eaad37bdf49c148d93002b4517ce0c7c104fbfd3)
Merge "Don't try to decode JSON request data if the request content length is null" into R1.10