fix: serialPort.open() failing

[codebytere]

Description of Change

Closes #35282.

Fixes an issue where serialPort.open() failed with NetworkError: Failed to open serial port..

This was happening because we returned nullptr from ElectronSerialDelegate::GetPortInfo:

electron/shell/browser/serial/electron_serial_delegate.cc

Lines 91 to 96 in 648c993

	const device::mojom::SerialPortInfo* ElectronSerialDelegate::GetPortInfo(
	content::RenderFrameHost* frame,
	const base::UnguessableToken& token) {
	// TODO(nornagon/jkleinsc): pass this on to the chooser context
	return nullptr;
	}

and SerialService::OpenPort expects that delegate->GetInfo returns non-null in order to succeed.

Tested with https://gist.github.com/17afc65be515f3a1aec6256cb69f069d and an Arduino Uno.

Checklist

• PR description included and stakeholders cc'd
• npm test passes
• relevant documentation is changed or added
• PR release notes describe the change in a way relevant to app developers, and are capitalized, punctuated, and past tense.

Release Notes

Notes: Fixed an issue where serialPort.open() failed with NetworkError: Failed to open serial port..

[release-clerk]

Release Notes Persisted

Fixed an issue where serialPort.open() failed with NetworkError: Failed to open serial port..

[trop]

I was unable to backport this PR to "20-x-y" cleanly;
you will need to perform this backport manually.

[trop]

I have automatically backported this PR to "21-x-y", please check out #35339