[webkit-changes] [WebKit/WebKit] 871bf5: Unreviewed, fix the build after rdar://115730279

[Wenson Hsieh]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 871bf5d743de06b4dcc2f769de87fadc261b3fd7
      https://github.com/WebKit/WebKit/commit/871bf5d743de06b4dcc2f769de87fadc261b3fd7
  Author: Wenson Hsieh <wenson_hsieh at apple.com>
  Date:   2023-10-11 (Wed, 11 Oct 2023)

  Changed paths:
    M Source/WTF/wtf/PlatformHave.h
    M Source/WebKit/NetworkProcess/cocoa/NetworkSessionCocoa.mm

  Log Message:
  -----------
  Unreviewed, fix the build after rdar://115730279

After the changes for rdar://115730279, libnetcore's `nw_proxy_config_create_with_agent_data` now
takes an additional nullable outparam. Add a compile-time guard for this version of the SPI, and
use it to soft link (and call the soft-linked function) with or without this extra argument.

* Source/WTF/wtf/PlatformHave.h:
* Source/WebKit/NetworkProcess/cocoa/NetworkSessionCocoa.mm:
(WebKit::NetworkSessionCocoa::setProxyConfigData):

Canonical link: https://commits.webkit.org/269221@main