[flags] Remove unused FLAG_randomize_hashes

Change-Id: I0df2943f246ea5dc8c56bb196c097dcdd58f1bea
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3308801Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78163}

src/flags/flag-definitions.h

@@ -1705,9 +1705,6 @@ DEFINE_BOOL(correctness_fuzzer_suppressions, false,
             "fuzzing: Abort program when the stack overflows or a string "
             "exceeds maximum length (as opposed to throwing RangeError). "
             "Use a fixed suppression string for error messages.")
-DEFINE_BOOL(randomize_hashes, true,
-            "randomize hashes to avoid predictable hash collisions "
-            "(with snapshots this option cannot override the baked-in seed)")
 DEFINE_BOOL(rehash_snapshot, true,
             "rehash strings from the snapshot to override the baked-in seed")
 DEFINE_UINT64(hash_seed, 0,

src/numbers/hash-seed-inl.h

@@ -39,7 +39,6 @@ inline uint64_t HashSeed(Isolate* isolate) {
 inline uint64_t HashSeed(ReadOnlyRoots roots) {
   uint64_t seed;
   roots.hash_seed().copy_out(0, reinterpret_cast<byte*>(&seed), kInt64Size);
-  DCHECK(FLAG_randomize_hashes || seed == 0);
   return seed;
 }