Remove RefCell from the definition and some uses of DefMap

[gereeter]

This is basically a more conservative recreation of #24096.

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @brson (or someone else) soon.

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[bors]

☔ The latest upstream changes (presumably #29564) made this pull request unmergeable. Please resolve the merge conflicts.

[alexcrichton]

r? @nrc (same reviewer on #29564)

[arielb1]

Q: Where is tcx::def_map borrowed mutably?
A: In astencode.

[nrc]

@bors: r+

[bors]

📌 Commit 7123834 has been approved by nrc

[nrc]

oh wait, needs a rebase

[gereeter]

Rebased.

[nrc]

@bors: r+

[bors]

📌 Commit b1788ef has been approved by nrc

[bors]

⌛ Testing commit b1788ef with merge 7839827...

[bors]

💔 Test failed - auto-win-gnu-32-nopt-t

[alexcrichton]

@bors: retry

On Wed, Nov 4, 2015 at 9:51 PM, bors notifications@github.com wrote:

[image: 💔] Test failed - auto-win-gnu-32-nopt-t
http://buildbot.rust-lang.org/builders/auto-win-gnu-32-nopt-t/builds/1979

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Reply to this email directly or view it on GitHub
#29581 (comment).

[bors]

⚡ Previous build results for auto-linux-32-nopt-t, auto-linux-32-opt, auto-linux-64-debug-opt, auto-linux-64-nopt-t, auto-linux-64-opt, auto-linux-cross-opt, auto-linux-musl-64-opt, auto-mac-32-opt, auto-mac-64-nopt-t, auto-mac-64-opt, auto-win-gnu-64-opt, auto-win-msvc-32-opt are reusable. Rebuilding only auto-linux-64-x-android-t, auto-win-gnu-32-nopt-t, auto-win-gnu-32-opt, auto-win-gnu-64-nopt-t, auto-win-msvc-64-opt...

[bors]

☀️ Test successful - auto-linux-32-nopt-t, auto-linux-32-opt, auto-linux-64-debug-opt, auto-linux-64-nopt-t, auto-linux-64-opt, auto-linux-64-x-android-t, auto-linux-cross-opt, auto-linux-musl-64-opt, auto-mac-32-opt, auto-mac-64-nopt-t, auto-mac-64-opt, auto-win-gnu-32-nopt-t, auto-win-gnu-32-opt, auto-win-gnu-64-nopt-t, auto-win-gnu-64-opt, auto-win-msvc-32-opt, auto-win-msvc-64-opt