[ruby-dev:49282] [Ruby trunk - Bug #10653] do-end block in ternary operator is syntax error

Issue #10653 has been updated by Tomoyuki Chikanaga.

Backport changed from 2.0.0: DONTNEED, 2.1: DONTNEED, 2.2: REQUIRED to 2.0.0: DONTNEED, 2.1: DONTNEED, 2.2: DONE

r50409, r51616, r51617 and r51624 were backported into `ruby_2_2` branch at r52046.
With r50409 a minor incompatibility is introduced ({ %w"key": 0 } cause SyntaxError).
I'm not confident the incompatibility is essential part of this fixes, but the accurate surgery is required to eliminate the incompatibility. I gave up.

----------------------------------------
Bug #10653: do-end block in ternary operator is syntax error 
https://bugs.ruby-lang.org/issues/10653#change-54367

* Author: Shinta Koyanagi
* Status: Closed
* Priority: Normal
* Assignee: Yukihiro Matsumoto
* ruby -v: ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
* Backport: 2.0.0: DONTNEED, 2.1: DONTNEED, 2.2: DONE
----------------------------------------
- For example

```
ruby -v -e 'true ? 1.tap do |n| p n end : 0'
```

- Result by 2.1.5

```
ruby 2.1.5p273 (2014-11-13 revision 48405) [x86_64-darwin14.0]
1
```

- Result by 2.2.0

```
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
-e:1: syntax error, unexpected keyword_do_cond, expecting ':'
true ? 1.tap do |n| p n end : 0
               ^
-e:1: syntax error, unexpected tIDENTIFIER, expecting keyword_do or '{' or '('
true ? 1.tap do |n| p n end : 0
                       ^
```



-- 
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