Fix Metadata aggregator: removing cumulative sum for GUIDs heap offset

[fabrimaz]

Removing cumulative sum for GUID heap offsets
Fixes #113910

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[fabrimaz]

Run unit-tests on this library:

=== TEST EXECUTION SUMMARY ===
System.Reflection.Metadata.Tests Total: 852, Errors: 0, Failed: 0, Skipped: 1, Time: 5,376s

[tmat]

The comment on line https://github.com/dotnet/runtime/pull/115268/files#diff-463bcba9d713f9c49493793a38b92567be4f344112abe18ebd08a34d3a5a1659R13 should be updated

[tmat]

It'd be good to have some tests that demonstrate correctness. There are some existing tests for MetadataAggregator, so you can update them. Make sure the test fails without your change and passes with the change.

[fabrimaz]

It'd be good to have some tests that demonstrate correctness. There are some existing tests for MetadataAggregator, so you can update them. Make sure the test fails without your change and passes with the change.

Hello! The linked comment was updated :)

The method "CalculateHeapSizes(..)" I edited is private and its result is assigned to a private field directly in the constructor of the class.
Even if I try to unit-test that constructor, I wouldn't be able to easily access the private field from unit-test class to assert its values.

What would you suggest? Should I split the mentioned method in a separate class to enhance testability?

Or else making the method 'internal'?