Import CoreExtension as a module

[paulb777]

• Address documentation build errors at iOS: Building documentation (Docc) gives error coming from FirebaseCoreExtension while building with Xcode 16 #13756 (comment)
• Fix iOS: Building documentation (Docc) gives error coming from FirebaseCoreExtension while building with Xcode 16 #13756

There are numerous build problems related to the headers in FirebaseCoreExtension being referenced by FirebaseCore and other modules caused by the headers being included twice from the two different contexts.

This PR addressed that by moving headers and implementations from FirebaseCoreExtension and FirebaseCore to FirebaseCoreInternal (FirebaseCoreInternalObjC for SPM).

Since FIRAppInternal.h and FIRHeartbeatLogger.h are intertwined with FIRApp.m, it's feasible to move them without a bigger refactor. In order for FIRHeartbeatLogger.h to build correctly, it cannot declare an enum, so the heartbeatCodeForToday API is converted to return an int.

Since this is an internal breaking change, the CocoaPods major version for the FIrebaseCore* podspecs need a bump to 12. The break is because early Firebase 11 pods float the minor FirebaseCore* versions.

We may want to make the next Firebase major version be 13 instead of 12, so we can resync the versions again.

The CI failures are either flakes are pending publishing the binary Analytics to staging.

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Commit: 440895f
Last updated: Mon Oct 28 20:06 PDT 2024
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[BUILD ERROR] FirebaseFirestore

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[ncooke3]

How can I reproduce the module building issues on main? I want to try a custom module map approach to remove the FirebaseCoreExtension entirely.

[paulb777]

@ncooke3 See the repro instructions at #13756 with the following Podfile:

platform :ios, '13.0'

source 'https://github.com/firebase/SpecsDev.git'
source 'https://github.com/firebase/SpecsStaging.git'
source 'https://cdn.cocoapods.org/'

target 'tempDoc' do
  # Comment the next line if you don't want to use dynamic frameworks
  use_frameworks!

  # Pods for tempDoc
     pod 'FirebaseCrashlytics', '11.5.0'
end

[paulb777]

Closing in favor of the much simpler solution in #13993