TBR: tools/lib/testutil: wrap "go generate" command in genXUnitReportOnCmdError (temporarily).
TBR: tools/lib/testutil: wrap "go generate" command in genXUnitReportOnCmdError (temporarily).

Final cleanup CL is coming.

Change-Id: Ib3685d0af4ace9798b0169e07d5c349ca1cdfd40

vanadium/go.devtools,vanadium/go.devtools,vanadium/go.devtools