The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/250918d769bb378b1152db5176a642499fbe4146

commit 250918d769bb378b1152db5176a642499fbe4146
Author: Giovanni Ortuño Urquidi <ortuno@chromium.org>
Date: Tue May 23 15:57:47 2017

bluetooth: Mark devices as disconnected when the adapter turns off

On macOS when the adapter turns off all devices are disconnected[1] but
didDisconnectPeripheral is not called by the OS.

This was causing us to think that the device was still connected,
keep around all its attributes and dispatch operations on the device
even though the device was disconnected.

Fixes the issue by calling didDisconnectPeripheral for each of our
connected BluetoothDevices.

[1] https://developer.apple.com/reference/corebluetooth/cbcentralmanagerdelegate/1518888-centralmanagerdidupdatestate?language=objc

Bug:  724300 , 511025
Change-Id: I1dc0f63fcf55949a4596f0ba05a87f158840df16
Reviewed-on: https://chromium-review.googlesource.com/511882
Commit-Queue: Giovanni Ortuño Urquidi <ortuno@chromium.org>
Reviewed-by: Vincent Scheib <scheib@chromium.org>
Cr-Commit-Position: refs/heads/master@{#473919}
[modify] https://crrev.com/250918d769bb378b1152db5176a642499fbe4146/device/bluetooth/bluetooth_adapter_mac.mm
[modify] https://crrev.com/250918d769bb378b1152db5176a642499fbe4146/device/bluetooth/bluetooth_adapter_unittest.cc
[modify] https://crrev.com/250918d769bb378b1152db5176a642499fbe4146/device/bluetooth/test/bluetooth_test.h
[modify] https://crrev.com/250918d769bb378b1152db5176a642499fbe4146/device/bluetooth/test/bluetooth_test_mac.h
[modify] https://crrev.com/250918d769bb378b1152db5176a642499fbe4146/device/bluetooth/test/bluetooth_test_mac.mm

ugh, still failing when refreshing the page.

Users experienced this crash on the following builds:

Mac Canary 60.0.3110.0 -  0.38 CPM, 1 reports, 1 clients (signature device::BluetoothRemoteGattCharacteristicMac::DidWriteValue)

If this update was incorrect, please add "Fracas-Wrong" label to prevent future updates.

- Go/Fracas

1. Device connects.
2. Write to a characteristic without response. (Which ends up posting a task to run DidWriteValue)
3. Immediately disconnect. (which causes macOS to mark the device as disconnected)
4. Crash. (DidWriteValue is ran which CHECKs that the device is connected, but since it isn't it crashes).

Code to reproduce the issue with a Playbulb. It might take a couple of tries:

  (async () => {
    console.log('yay');

    let device = await navigator.bluetooth.requestDevice({
      filters:[{services: [0xff02]}]
    });

    await device.gatt.connect();
\
    let service = await device.gatt.getPrimaryService(0xff02);
 
    let characteristic = await service.getCharacteristic(0xfffc);
 
    characteristic.writeValue(new Uint8Array([0xff, 0x88, 0x88, 0x88]));
    device.gatt.disconnect();
  })();

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/9383c369577ba6704d02c6827f12dbbab7b28b55

commit 9383c369577ba6704d02c6827f12dbbab7b28b55
Author: Giovanni Ortuño Urquidi <ortuno@chromium.org>
Date: Fri May 26 15:37:47 2017

bluetooth: Flush pending writes without response callbacks if we disconnected

The problem:
1. Device connects.
2. Write to a characteristic without response. (Which ends up posting a task to run DidWriteValue)
3. Immediately disconnect. (which causes macOS to mark the device as disconnected)
4. Crash. (DidWriteValue is ran which CHECKs that the device is connected, but since it is it crashes).

Flushes all pending writes when DidWriteValue is called and the device is disconnected.

Bug:  724300 
Change-Id: I6cb0fd640e313733297ae093f45bdaa8dfe71a67
Reviewed-on: https://chromium-review.googlesource.com/516487
Reviewed-by: Vincent Scheib <scheib@chromium.org>
Commit-Queue: Giovanni Ortuño Urquidi <ortuno@chromium.org>
Cr-Commit-Position: refs/heads/master@{#475008}
[modify] https://crrev.com/9383c369577ba6704d02c6827f12dbbab7b28b55/device/bluetooth/bluetooth_remote_gatt_characteristic_mac.mm
[modify] https://crrev.com/9383c369577ba6704d02c6827f12dbbab7b28b55/device/bluetooth/bluetooth_remote_gatt_characteristic_unittest.cc
[modify] https://crrev.com/9383c369577ba6704d02c6827f12dbbab7b28b55/device/bluetooth/test/mock_bluetooth_central_manager_mac.mm

hmm this missed the branch point. We should ask for merge once it has been on canary for a day.

Your change meets the bar and is auto-approved for M60. Please go ahead and merge the CL to branch 3112 manually. Please contact milestone owner if you have questions.
Owners: amineer@(Android), cmasso@(iOS), josafat@(ChromeOS), bustamante@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Thanks for the fix. 

Please confirm whether the fix is verified in canary. If yes, merge to 3112 branch before 4.00 PM PST(05/31) to make it to next release.

I already cherry picked the patch but for some reason it didn't show up here.

https://chromium-review.googlesource.com/c/517453/

I set the label manually.