Fix SettingsIncidentTest#testBasicStructure

When writing to a nested message field using ProtoOutputStream, need
to call ProtoOutputStream#start() before and ProtoOutputStream#end()
after.

Fixes: 146684453
Test: atest CtsIncidentHostTestCases SettingsIncidentTest#testBasicStructure
Change-Id: Ib4b858ec74c400c6d2ba78d1aca02b2d2102235b
1 file changed