Add float32-blendable feature validation tests

[beaufortfrancois]

This PR adds "float32-blendable" feature validation tests to the CTS after it was added to the spec in gpuweb/gpuweb#4896.

It currently requires Chromium patched with https://dawn-review.googlesource.com/c/dawn/+/210754 and https://chromium-review.googlesource.com/c/chromium/src/+/5929023

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Requirements for PR author:

• All missing test coverage is tracked with "TODO" or .unimplemented().
• New helpers are /** documented */ and new helper files are found in helper_index.txt.
• Test behaves as expected in a WebGPU implementation. (If not passing, explain above.)
• Test have be tested with compatibility mode validation enabled and behave as expected. (If not passing, explain above.)

Requirements for reviewer sign-off:

• Tests are properly located in the test tree.
• Test descriptions allow a reader to "read only the test plans and evaluate coverage completeness", and accurately reflect the test code.
• Tests provide complete coverage (including validation control cases). Missing coverage MUST be covered by TODOs.
• Helpers and types promote readability and maintainability.

When landing this PR, be sure to make any necessary issue status updates.

[beaufortfrancois]

Thank you Kai!

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On Wed, Oct 16, 2024, 06:22 Kai Ninomiya ***@***.***> wrote: Merged #4003 <#4003> into main. — Reply to this email directly, view it on GitHub <#4003 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAE243WQBOQ4AKALBRHST7LZ3XSZZAVCNFSM6AAAAABP62ZOJGVHI2DSMVQWIX3LMV45UABCJFZXG5LFIV3GK3TUJZXXI2LGNFRWC5DJN5XDWMJUGY3DOOJXGE2DANI> . You are receiving this because you authored the thread.Message ID: ***@***.***>