Stop using a RefPtr<IPC::Connection> as HashMap key in DisplayLink

[Chris Dumez]

Stop using a RefPtr<IPC::Connection> as HashMap key in DisplayLink. Using a RefPtr as key is suboptimal and could leak to memory leaks.
We now store IPC::Connection::UniqueID instead and look up the IPC::Connection from its identifier when we need to send an IPC.

[Chris Dumez]

Created attachment 430421 [details]
Patch

[Simon Fraser (smfr)]

Comment on attachment 430421 [details]
Patch

Great!

[EWS]

Committed r278395 (238420@main): <https://commits.webkit.org/238420@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 430421 [details].

[Radar WebKit Bug Importer]

<rdar://problem/78798133>

[Kimmo Kinnunen]

This patch is not defined C++.

Single-threaded id to instance lookup can be implemented by maintaining the id map in constructor and destructor.

Multi-threaded id to instance lookup cannot be implemented by maintaining the id map in the constructor and destructor. One thread might do a lookup while other thread might have already entered into the destructor, ending the life-time of the object.

[Kimmo Kinnunen]

Comment on attachment 430421 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=430421&action=review

> Source/WebKit/Platform/IPC/Connection.cpp:309
>  

one thread here, object life time has ended

> Source/WebKit/Platform/IPC/Connection.h:530
> +    return connection->send(WTFMove(message), destinationID, sendOptions);

other thread here, using object that is not alive anymore