[release/8.0-staging] Fix return in zlib-intel when window allocation fails

[ericstj]

Customer Impact

• Customer reported
• Found internally

If a process is running low on memory and fails window allocation in zlib on Windows, we weren't correctly returning the error to produce the correct ZlibException. This creates a reliability issue as the failure looks like an application crash instead of out of memory. This issue is unique to the zlib-intel codebase.

Regression

• Yes
• No

Testing

Unit tests, adhoc testing.

Risk

Low. This is likely a non-recoverable error, we're just making sure we surface in a way that diagnostics will correctly capture.

[Copilot]

Pull Request Overview

This PR addresses a reliability issue by ensuring inflate.c returns Z_MEM_ERROR immediately when window allocation fails, allowing the proper exception to surface instead of leading to a crash.

• Converted deferred ret = Z_MEM_ERROR assignments to immediate return Z_MEM_ERROR in two error paths.
• Ensures out-of-memory conditions produce the correct error response in zlib-intel on Windows.

Comments suppressed due to low confidence (2)

src/native/external/zlib-intel/inflate.c:254

• Add or update unit tests to simulate window allocation failures and verify that Z_MEM_ERROR is returned and a ZlibException is thrown as expected.

return Z_MEM_ERROR;

src/native/external/zlib-intel/inflate.c:730

• Ensure tests cover this second allocation failure path to confirm consistent error handling in both branches.

return Z_MEM_ERROR;

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