Remove uses of Build across Builder steps

[Mark-Simulacrum]

This is purely a code cleanup; there should be no functional changes.

r? @alexcrichton

[rust-highfive]

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.

[00:00:46] configure: rust.quiet-tests := True
---
[00:05:43] tidy error: /checkout/src/bootstrap/native.rs:495: line longer than 100 chars
[00:05:43] tidy error: /checkout/src/bootstrap/dist.rs:623: line longer than 100 chars
[00:05:43] tidy error: /checkout/src/bootstrap/dist.rs:789: line longer than 100 chars
[00:05:43] tidy error: /checkout/src/bootstrap/compile.rs:361: line longer than 100 chars
[00:05:45] some tidy checks failed
[00:05:45]
[00:05:45]
[00:05:45] 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"
[00:05:45] expected success, got: exit code: 1
[00:05:45]
[00:05:45]
[00:05:45] failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test src/tools/tidy
[00:05:45] Build completed unsuccessfully in 0:02:28
[00:05:45] Makefile:79: recipe for target 'tidy' failed
[00:05:45] make: *** [tidy] Error 1
---
$ ls -lat $HOME/Library/Logs/DiagnosticReports/
ls: cannot access /home/travis/Library/Logs/DiagnosticReports/: No such file or directory
travis_time:end:0742b226:start=1523749012108052664,finish=1523749012114153619,duration=6100955
travis_fold:end:after_failure.2
travis_fold:start:after_failure.3
travis_time:start:0b91b1f8
$ find $HOME/Library/Logs/DiagnosticReports -type f -name '*.crash' -not -name '*.stage2-*.crash' -not -name 'com.apple.CoreSimulator.CoreSimulatorService-*.crash' -exec printf travis_fold":start:crashlog\n\033[31;1m%s\033[0m\n" {} \; -exec head -750 {} \; -exec echo travis_fold":"end:crashlog \; || true
find: `/home/travis/Library/Logs/DiagnosticReports': No such file or directory
travis_time:end:0b91b1f8:start=1523749012119908767,finish=1523749012126093756,duration=6184989
travis_fold:end:after_failure.3
travis_fold:start:after_failure.4
travis_time:start:1103a09f
$ dmesg | grep -i kill
[ 10.569401] init: failsafe main process (1091) killed by TERM signal

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[alexcrichton]

@bors: r+

Nice!

[bors]

📌 Commit 72e2ece has been approved by alexcrichton

[bors]

☔ The latest upstream changes (presumably #49542) made this pull request unmergeable. Please resolve the merge conflicts.

[Mark-Simulacrum]

@bors r=alexcrichton

[bors]

📌 Commit be1e789 has been approved by alexcrichton

[bors]

⌛ Testing commit be1e789 with merge 23561c6...

[bors]

☀️ Test successful - status-appveyor, status-travis
Approved by: alexcrichton
Pushing 23561c6 to master...