Update Electron to 1.6.10

[yuya-oc]

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Summary
Update Electron to v1.6.10. This is the prior work for #525.

Electron 1.6.7 supports following features for Windows. So this PR should test them.

• Desktop notification for Windows 7
• Per-monior DPI awareness

Issue link
#67, #357

Test Cases
Notification:

1. Prepare Windows 7, 8 or 8.1
2. Receive any message.
3. Notification should appear instead of a tray balloon.
4. Click the notification.
5. The message should appear in the main window as well as Windows 10.

Per-monitor DPI:

1. Prepare Windows 8.1 or 10
2. Connect two monitors and set different DPI scaling.
3. Move the window across monitors.
4. The window should be rendered in proper DPI.

Additional Notes
https://circleci.com/gh/yuya-oc/desktop/268#artifacts

[jasonblais]

I tested desktop notifications on Windows 10, works as expected. I'll ask a team member to help with Windows 7.

I only have one monitor so I can't test the second improvement..I'm not sure if you're able to?

[lindy65]

I tested desktop notifications on Windows 7.

While desktop notifications work as expected for direct messages and public channels, they do not appear for messages or at mentions sent in private channels, even though I am a member of the channel and have notifications set to "all activity".

Although the desktop notification does not fire for private channels, the channel is bolded and shows number of mentions.

[yuya-oc]

I tested per-monitor DPI. It looks fine also on the secondary monitor.

Case 1: Primary 150%, Secondary 100%

v3.7.0 on 100%

PR on 100%

Case 2: Primary 100%, Secondary 150%

v3.7.0 on 150%

PR on 150%

[jasonblais]

@yuya-oc Lindy helped test on the browser and the issue she reports reproduces on Chrome as well

So we should be okay to merge this PR

[razzeee]

Would there be interest in moving this application to typescript? As Electron now bundles the definitions? https://electron.atom.io/blog/2017/06/01/typescript

[yuya-oc]

Sounds nice, but probably there are not enough time to move for me, so currently no. I feel we should consider to improve code structure rather than that.

(And I have no experience in TypeScript)

[yuya-oc]

@jasonblais @lindy65 Thanks for testing!

[lindy65]

Pleasure @yuya-oc! Anytime :)