Several updates to fuzz tests, including http://go/wvgerrit/124043 Add documentation for partners to run fuzzing http://go/wvgerrit/128224 Fix generic verify fuzz script http://go/wvgerrit/120507 Fuzzing: Add fuzzer for reportusage API http://go/wvgerrit/120503 Fuzzing: Add fuzzer for deactivate usageentry API http://go/wvgerrit/120463 Fuzzing: Add logic to exit fuzzer script http://go/wvgerrit/120444 Fuzzing: Add fuzzer for loadusageentry API Bug: 183154879 Bug: 202994773 Bug: 186785830 Test: test only code Change-Id: I877681461824c51bc82f0766a9973378aafadba7