[PLAT-8219] Fix crash when using BugsnagNetworkRequestPlugin alongside New Relic

[nickdowell]

Goal

Fix a crash that occurs when BugsnagNetworkRequestPlugin is linked into a project that uses the New Relic.

Sample crash:

2022-03-25 12:00:40.842579+0000 NetApp[27482:2012467] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[NSProxy doesNotRecognizeSelector:URLSession:downloadTask:didWriteData:totalBytesWritten:totalBytesExpectedToWrite:] called!'
*** First throw call stack:
(
	0   CoreFoundation                      0x00007fff203feba4 __exceptionPreprocess + 242
	1   libobjc.A.dylib                     0x00007fff201a1be7 objc_exception_throw + 48
	2   Foundation                          0x00007fff208184c2 +[NSProxy instanceMethodSignatureForSelector:] + 0
	3   CoreFoundation                      0x00007fff204030ac ___forwarding___ + 1433
	4   CoreFoundation                      0x00007fff204051d8 _CF_forwarding_prep_0 + 120
	5   CFNetwork                           0x00007fff23e164e5 _CFHostIsDomainTopLevelForCertificatePolicy + 29799
	6   Foundation                          0x00007fff207e24bb __NSBLOCKOPERATION_IS_CALLING_OUT_TO_A_BLOCK__ + 7
	7   Foundation                          0x00007fff207e23b3 -[NSBlockOperation main] + 98
	8   Foundation                          0x00007fff207e53c3 __NSOPERATION_IS_INVOKING_MAIN__ + 17
	9   Foundation                          0x00007fff207e1600 -[NSOperation start] + 785
	10  Foundation                          0x00007fff207e5d17 __NSOPERATIONQUEUE_IS_STARTING_AN_OPERATION__ + 17
	11  Foundation                          0x00007fff207e585c __NSOQSchedule_f + 182
	12  libdispatch.dylib                   0x00000001068bfa76 _dispatch_block_async_invoke2 + 83
	13  libdispatch.dylib                   0x00000001068b0a2c _dispatch_client_callout + 8
	14  libdispatch.dylib                   0x00000001068b73a6 _dispatch_lane_serial_drain + 845
	15  libdispatch.dylib                   0x00000001068b80f2 _dispatch_lane_invoke + 490
	16  libdispatch.dylib                   0x00000001068b71c7 _dispatch_lane_serial_drain + 366
	17  libdispatch.dylib                   0x00000001068b80bc _dispatch_lane_invoke + 436
	18  libdispatch.dylib                   0x00000001068c4472 _dispatch_workloop_worker_thread + 900
	19  libsystem_pthread.dylib             0x00007fff6da2845d _pthread_wqthread + 314
	20  libsystem_pthread.dylib             0x00007fff6da2742f start_wqthread + 15
)

Changeset

Uses the lighter-weight forwardingTargetForSelector: mechanism instead of implementing methodSignatureForSelector: and forwardInvocation:.

It's not entirely clear why this fixes the crash, but it does in the example app used, and is also faster 🚀

New Relic's session delegate implements forwardingTargetForSelector: rather than forwardInvocation: and the crash presumably arose because of the mismatch.

Testing

Reproduced the crash by creating an example app that uses BugsnagNetworkRequestPlugin, New Relic, and initiates a download task using Moya.

[github-actions]

Bugsnag.framework binary size did not change - 857,312 bytes

    FILE SIZE        VM SIZE    
 --------------  -------------- 
  [ = ]       0  [ = ]       0    TOTAL

Generated by 🚫 Danger

[kstenerud]

I'm cool with this as long as we're sure it's not going to break other library integrations.

This proxy stuff is always ugly...