* Address #7631 by correctly pooling large-capacity buffers
As the issue states, `mem.NewBuffer` would not pool buffers with a length below
the pooling threshold but whose capacity is actually larger than the pooling
threshold. This can lead to buffers being leaked.
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Co-authored-by: Purnesh Dixit <purneshdixit@google.com>
Co-authored-by: Easwar Swaminathan <easwars@google.com>