Simplify the returning of a Result a bit

[janhohenheim]

No description provided.

[rust-highfive]

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[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:1be0d33c:start=1555511561041899128,finish=1555511563287386925,duration=2245487797
$ 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
$ export GCP_CACHE_BUCKET=rust-lang-ci-cache
$ export AWS_ACCESS_KEY_ID=AKIA46X5W6CZEJZ6XT55
---
[00:05:13]    Compiling panic_unwind v0.0.0 (/checkout/src/libpanic_unwind)
[00:05:14] error[E0423]: expected value, found struct `File`
[00:05:14]    --> src/libstd/fs.rs:904:47
[00:05:14]     |
[00:05:14] 904 |         fs_imp::File::open(path, &self.0).map(File)
[00:05:14]     |                                               ^^^^ did you mean `File { /* fields */ }`?
[00:05:14]     |
[00:05:14] 10  | use crate::sys::unix::fs::File;
[00:05:14]     |
[00:05:14] 
---
travis_time:end:06716e32:start=1555511891775138881,finish=1555511891780816641,duration=5677760
travis_fold:end:after_failure.3
travis_fold:start:after_failure.4
travis_time:start:09666163
$ 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:0f698b96
travis_time:start:0f698b96
$ 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:2b4918ac
$ 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)

[shepmaster]

Looks reasonable to me — please go ahead and squash those commits and we can merge this.

[janhohenheim]

@shepmaster done 👍

[shepmaster]

@bors r+ rollup

[bors]

📌 Commit 379c541 has been approved by shepmaster