Ignore should_panic tests on android

[Mark-Simulacrum]

These tests currently segfault sometimes. Android is a tier-2 target so
this is fine to disable instead of fixing.

Unfortunately, this isn't quite enough as rustdoc doesn't currently
correctly interpret the --exclude-should-panic flag (i.e., ignores it).
That proved to be harder to fix than I had time for so we're going to
leave it and hope that at least some of the failures are fixed.

Hopefully alleviates #55861; I don't have the time to investigate fixing rustdoc.

[Mark-Simulacrum]

r? @kennytm

[Mark-Simulacrum]

I will also note that I have not tested that this code works locally beyond "it compiles" but it looks like it should do what we want it to.

[rust-highfive]

The job x86_64-gnu-llvm-6.0 of your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

travis_time:end:3014fc89:start=1551634956566190579,finish=1551634957417205320,duration=851014741
$ git checkout -qf FETCH_HEAD
travis_fold:end:git.checkout

Encrypted environment variables have been removed for security reasons.
See https://docs.travis-ci.com/user/pull-requests/#pull-requests-and-security-restrictions
$ export SCCACHE_BUCKET=rust-lang-ci-sccache2
$ export SCCACHE_REGION=us-west-1
Setting environment variables from .travis.yml
$ export IMAGE=x86_64-gnu-llvm-6.0
---

[00:04:00] travis_fold:start:tidy
travis_time:start:tidy
tidy check
[00:04:00] tidy error: /checkout/src/bootstrap/config.rs:658: line longer than 100 chars
[00:04:02] some tidy checks failed
[00:04:02] 
[00:04:02] 
[00:04:02] command did not execute successfully: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-tools-bin/tidy" "/checkout/src" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin/cargo" "--no-vendor" "--quiet"
[00:04:02] 
[00:04:02] 
[00:04:02] failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test src/tools/tidy
[00:04:02] Build completed unsuccessfully in 0:00:47
[00:04:02] Build completed unsuccessfully in 0:00:47
[00:04:02] Makefile:68: recipe for target 'tidy' failed
[00:04:02] make: *** [tidy] Error 1
The command "stamp sh -x -c "$RUN_SCRIPT"" exited with 2.
travis_time:start:00eb4e50
$ date && (curl -fs --head https://google.com | grep ^Date: | sed 's/Date: //g' || true)
Sun Mar  3 17:46:50 UTC 2019
---
travis_time:end:0705dc00:start=1551635211476902897,finish=1551635211482467540,duration=5564643
travis_fold:end:after_failure.3
travis_fold:start:after_failure.4
travis_time:start:21fac980
$ ln -s . checkout && for CORE in obj/cores/core.*; do EXE=$(echo $CORE | sed 's|obj/cores/core\.[0-9]*\.!checkout!\(.*\)|\1|;y|!|/|'); if [ -f "$EXE" ]; then printf travis_fold":start:crashlog\n\033[31;1m%s\033[0m\n" "$CORE"; gdb --batch -q -c "$CORE" "$EXE" -iex 'set auto-load off' -iex 'dir src/' -iex 'set sysroot .' -ex bt -ex q; echo travis_fold":"end:crashlog; fi; done || true
travis_fold:end:after_failure.4
travis_fold:start:after_failure.5
travis_time:start:1ada93cc
travis_time:start:1ada93cc
$ cat ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers || true
cat: ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers: No such file or directory
travis_fold:end:after_failure.5
travis_fold:start:after_failure.6
travis_time:start:03c23c64
$ dmesg | grep -i kill

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

[kennytm]

r=me after fixing tidy.

[Mark-Simulacrum]

@bors r=kennytm

[bors]

📌 Commit 1055263 has been approved by kennytm

[Centril]

Probably failed in #59043 (comment), @bors r-

[kennytm]

We don't need -Z unstable-options?

[Mark-Simulacrum]

I suspect it's being passed to the wrong tool. I'll try to investigate further today.

[TimNN]

Ping from triage @Mark-Simulacrum: What is the status of this PR?

[Mark-Simulacrum]

I will try to get back to this sometime this week.

[Mark-Simulacrum]

I don't think I'll have the time soon to take this on unfortunately so I'm going to close this.