Clarify the short explanation of E0207

[nickolay]

After being greatly improved in #33692, https://doc.rust-lang.org/error-index.html#E0207 uses terminology from the related RFC, which is different from the reference, e.g. "self type" instead of "implementing type" and "trait reference" instead of "implemented trait".

It probably makes no difference to an experienced reader, but for a newbie like me it added to the confusion as you can't look up the definition of the terms being used and can't be sure you've guessed correctly...

I would also move the link to RFC to the top, as it seems to be the only doc that attempts to explain what the third criteria entails), but it seems to go against the accepted style.

[rust-highfive]

Some changes occurred in diagnostic error codes

cc @GuillaumeGomez

[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.

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travis_time:end:02546b1f:start=1556480162141635027,finish=1556480163627633299,duration=1485998272
$ 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
---
[00:04:02] tidy error: /checkout/src/librustc_typeck/error_codes.rs:1947: trailing whitespace
[00:04:04] some tidy checks failed
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[00:04:04] 
[00:04:04] 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"
[00:04:04] 
[00:04:04] 
[00:04:04] failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test src/tools/tidy
[00:04:04] Build completed unsuccessfully in 0:00:44
[00:04:04] Build completed unsuccessfully in 0:00:44
[00:04:04] Makefile:67: recipe for target 'tidy' failed
[00:04:04] make: *** [tidy] Error 1
The command "stamp sh -x -c "$RUN_SCRIPT"" exited with 2.
travis_time:start:15954d91
$ date && (curl -fs --head https://google.com | grep ^Date: | sed 's/Date: //g' || true)
Sun Apr 28 19:40:19 UTC 2019
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travis_time:end:01e1d756:start=1556480420013082555,finish=1556480420017615071,duration=4532516
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travis_time:start:00520404
$ 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
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travis_time:start:0bd4d7b8
travis_time:start:0bd4d7b8
$ 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
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$ dmesg | grep -i kill

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[GuillaumeGomez]

Thanks!

@bors: r+ rollup

[bors]

📌 Commit 35f1c2f has been approved by GuillaumeGomez