Add random Device ID generation
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The [spec](https://webbluetoothcg.github.io/web-bluetooth/#add-an-allowed-bluetooth-device) (2. step) defines that the device id can't be the public address, therefore we generate a random id.
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- [ ] There are tests for these changes OR
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Changes include:
- Introduce an IpcSend trait to abstract over a collection of IpcSenders
- Implement ResourceThreads collection to abstract the resource-related
sub threads across the component
- Rename original ResourceThread and ControlMsg into an unifed CoreResource__
to accommodate above changes and avoid confusions
Add FileManagerThread
This is intended to support the File API implementation. Basically an event loop with three kinds of messages:
+ Select a file
+ Read a file with ID
+ Delete the ID from manager-owned map
The design decision in this PR is not the final (or best I think) version, welcome reviews :)
TODOs:
- [x] Add multiple file selection
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WebRender has many bugs, and missing features - but it is usable to browse most websites - please report any WebRender specific rendering bugs you encounter!
