Fix apps using Adobe AIR.

Apps that use Adobe AIR are all broken because the symbol
_ZN7android9OMXClient7connectEv disappeared. If we use overloading
for OMXClient::connect rather than a default parameter, that gives
us another release to reach out to the app authors.

Bug: http://b/35325668
Bug: http://b/35454864
Bug: http://b/36106661
Bug: http://b/36263763
Bug: http://b/36501801
Bug: http://b/37176992
Test: ran broken apps
Change-Id: Ic310fc0e69be322f007601d23bb4bf82df215036