Re: [web-bluetooth] Provide a way to pair when the user's paying attention

Here's what I get on macOS when connecting my MX Master mouse from 
https://googlechrome.github.io/samples/web-bluetooth/device-disconnect.html?namePrefix=MX:

```
...
Feb 01 10:44:09.240     ATT Send        FC:E9:FE:31:4E:62       0x0040
  Read Request - Handle:0x0021
Feb 01 10:44:09.740     ATT Receive     FC:E9:FE:31:4E:62       0x0040
  Error Response - Attribute Handle: 0x0021 - Error Code: 0x05
Feb 01 10:44:09.741     SMP Send        FC:E9:FE:31:4E:62       0x0040
  LE SMP Pairing Request Command 
Feb 01 10:44:09.763     SMP Receive     FC:E9:FE:31:4E:62       0x0040
  LE SMP Pairing Response Command 
Feb 01 10:44:09.764     SMP Send        FC:E9:FE:31:4E:62       0x0040
  LE SMP Pairing Confirm Command 
Feb 01 10:44:09.785     SMP Receive     FC:E9:FE:31:4E:62       0x0040
  LE SMP Pairing Confirm Command 
Feb 01 10:44:09.937     SMP Send        FC:E9:FE:31:4E:62       0x0040
  LE SMP Pairing Random Command 
Feb 01 10:44:10.314     SMP Receive     FC:E9:FE:31:4E:62       0x0040
  LE SMP Pairing Random Command 
Feb 01 10:44:10.438     HCI COMMAND     00:00:00:00:00:00       0x401C
  [2019] LE Start Encryption - Connection Handle: 0x0040
Feb 01 10:44:10.439     HCI EVENT       00:00:00:00:00:00       0x0000
  Command Status - LE Start Encryption
...
```

For info, full log are available at http://pastebin.com/raw/XS3xVMfM

The Error Code 0x05 is `BLE_HCI_AUTHENTICATION_FAILURE` which 
indicates that when macOS tries to discover all 
services/characteristics/descriptors, it stumbles upon one that 
requires authentication and simply triggers the SMP Pairing Request.

-- 
GitHub Notification of comment by beaufortfrancois
Please view or discuss this issue at 
https://github.com/WebBluetoothCG/web-bluetooth/issues/137#issuecomment-276617705
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Received on Wednesday, 1 February 2017 10:01:36 UTC