[sidebar]Double click new file make all files display grey

[oDoraemon]

Issue Type: Bug

Double Click new file icon in sidebar get all files grey

VS Code version: Code 1.22.1 (950b8b0, 2018-04-06T02:26:57.615Z)

Extensions (4)

Extension	Author (truncated)	Version
vscode-eslint	dba	1.4.8
php-intellisense	fel	2.3.1
php-pack	fel	1.0.1
python	ms-	2018.3.1

[joaomoreno]

@isidorn Setting candidate for discussion.

[isidorn]

I can reproduce it and it is a regression.
However the issue is of cosmetic nature the explroer is gray and no other behavior is broken. Also the bad behavior goes away if a user clicks on a new file icon again or if he restarts vscode.
Due to the above I belive this is not a candidate. @joaomoreno @bpasero let me know if you disagree and I can look into fixing it for the recovery

[isidorn]

This got introduced because we switched to use a map instead of an array for children.
So the NewStatPlaceholder would get ovewritten in the map.
Fix: made the new file / new folder actions noop when the parent is in the process of creating a new entry