Wrong coloration for commented multiple line string block

[maxime915]

Prerequisites

• [X] Put an X between the brackets on this line if you have done all of the following:
  • Reproduced the problem in Safe Mode: http://flight-manual.atom.io/hacking-atom/sections/debugging/#using-safe-mode
  • Followed all applicable steps in the debugging guide: http://flight-manual.atom.io/hacking-atom/sections/debugging/
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Description

Editing a .yml file, commenting a multiple line text block will not show correctly (I checked will multiples theme to be sure), this might be an issue of the langage-yml package. To be clear, only the line "# blockname: >" doesn't get gray, all the other line are normally commented, however executing the file, the block is commented, this is juste a presentation issue.

Steps to Reproduce

1. create a YAML file
2. create a commented block with multiple line, exemple:

   test:
   path: /path
   defaults:
   _controller: Bundle:Default:Action
   # condition: >
   #   request.headers.get('firstHeader') != null and
   #   request.headers.get('secondHeader') != null and
   #   request.headers.get('thirdHeader') != null

3. Look at the wrong coloration

Expected behavior: The first commented line should be also grey

Actual behavior: The first commented line is not also grey, it event appear on the web preview

Atom:

Web:

Reproduces how often: everytime I do it

Versions

Atom : 1.19.5 Electron: 1.6.9 Chrome : 56.0.2924.87 Node : 7.4.0