Build tor fuzzing binaries with static libevent linkage

[nmathewson]

Apparently libevent.so is not available on the execution environment. This change statically links that library.

(More information about the bug on #265 (comment) )

[googlebot]

We found a Contributor License Agreement for you (the sender of this pull request), but were unable to find agreements for the commit author(s). If you authored these, maybe you used a different email address in the git commits than was used to sign the CLA (login here to double check)? If these were authored by someone else, then they will need to sign a CLA as well, and confirm that they're okay with these being contributed to Google.

[kcc]

maybe link all of the libs statically? (it might be required, we are checking that now).

Apparently you commit the patches into the branch under a different user name.
May I ask you to do something with the CLA? (either sign the CLA with that user name too, or commit the patches under this user name).

[nmathewson]

I just added [email protected] to the CLA -- please let me know if I did it wrong.

[googlebot]

CLAs look good, thanks!

[kcc]

The bot is happy with the CLA now.
I can merge it as is and see if it helps, or you may links more libs statically first. Your call.

[nmathewson]

Let's try this one; I think the rest of the things are standard enough that it has a decent chance of working.

[inferno-chromium]

After @mikea fix 6f23387, fuzzers are not longer crashing.

When you have time, please fix this so that builds stop showing unstable on
https://oss-fuzz-build-logs.storage.googleapis.com/status.html

https://clusterfuzz-external.appspot.com/v2/testcase-detail/6432660930953216

==70==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 33 byte(s) in 1 object(s) allocated from:
#0 0x463ea0 in _interceptor_strdup /src/llvm/projects/compiler-rt/lib/asan/asan_interceptors.cc:550
#1 0xecce90 in tor_strdup /src/tor/src/common/util.c:288:15
#2 0x667042 in fuzz_main /src/tor/src/test/fuzz/fuzz_http.c:105:28
#3 0x665943 in LLVMFuzzerTestOneInput /src/tor/src/test/fuzz/fuzzing_common.c:129:10
#4 0x587af8 in fuzzer::Fuzzer::ExecuteCallback(unsigned char const*, unsigned long) /src/libfuzzer/FuzzerLoop.cpp:546:13
#5 0x586cbd in fuzzer::Fuzzer::ShuffleAndMinimize(std::__1::vector<std::__1::vector<unsigned char, std::__1::allocator >, std::__1::allocator<std::__1::vector<unsigned char, std::__1::allocator > > >) /src/libfuzzer/FuzzerLoop.cpp:473:3
#6 0x520e68 in fuzzer::FuzzerDriver(int, char***, int ()(unsigned char const, unsigned long)) /src/libfuzzer/FuzzerDriver.cpp:534:6
#7 0x513ca8 in main /src/libfuzzer/FuzzerMain.cpp:20:10
#8 0x7fa74ff4682f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2082f)

SUMMARY: AddressSanitizer: 33 byte(s) leaked in 1 allocation(s).
MS: 0 ; base unit: 0000000000000000000000000000000000000000

artifact_prefix='./'; Test unit written to ./crash-da39a3ee5e6b4b0d3255bfef95601890afd80709