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0acc8470116819a62fd5ebbc2c64fdd703c93331 by Abseil Team <absl-team@google.com>:

Add an attribute to HashtablezInfo which performs a bitwise XOR on all hashes. The purposes of this attribute is to identify if identical hash tables are being created. If we see a large number of identical tables, it's likely the code can be improved by using a common table as opposed to keep rebuilding the same one.

PiperOrigin-RevId: 356338043
GitOrigin-RevId: 0acc8470116819a62fd5ebbc2c64fdd703c93331
Change-Id: If7d0a96629144fb41e6bef1ec93345a22df40733