Incorrect indentation when using flow and tree-sitter

[IanVS]

Prerequisites

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  • 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

I originally opened this in atom/language-javascript#603. Duplicating here, since this seems to be the grammar being used.

When using the Flow Javascript grammar with tree-sitter enabled, I notice that parenthesis are not always outdented correctly, whereas they are when using Javascript. Here are some examples (taken during safe mode):

Javascript (correct)

Flow Javascript (incorrect)

Steps to Reproduce

1. Create a file with the flow pragma
2. Verify the grammar shows as Flow Javascript
3. Notice that indentation is wonky, as shown in the gif above.

Expected behavior: [What you expect to happen]
I expect the closing parenthesis to be on the same column as the first character of the line with the opening parenthesis.

Actual behavior: [What actually happens]
The closing parens is indented by one level, to the same position as the cursor.

Reproduces how often: [What percentage of the time does it reproduce?]
100%

Versions

You can get this information from copy and pasting the output of atom --version and apm --version from the command line. Also, please include the OS and what version of the OS you're running.

Atom : 1.32.0-beta3
Electron: 2.0.9
Chrome : 61.0.3163.100
Node : 8.9.3
apm 2.1.2
npm 6.2.0
node 8.9.3 x64
atom 1.32.0-beta3
python 2.7.10
git 2.19.1

[IanVS]

Also, I have to say, it's more than a little confusing that the language-typescript grammar is used to handle flow.