Do not place "failureInfo" of JSON of non-failing test
Do not place "failureInfo" of JSON of non-failing test

Summary:
Where there is no failureInfo returned from the protobuf, we shouldn't include this in the output.

`None` is not the valid check here because protobufs will initialize structs, with members that are defaulted to 0/empty string.

Reviewed By: jbardini

Differential Revision: D29875359

fbshipit-source-id: c731d8912d573e1d8769a93bc8c29c11b9e38cfd

facebook/FBSimulatorControl,facebook/FBSimulatorControl,facebook/FBSimulatorControl,facebook/FBSimulatorControl,facebook/FBSimulatorControl