Changes imported from Abseil "staging" branch:

  - a0405e7870a80a9dbc6784b06795e7df5a8c90f5 Internal change by Daniel Katz <katzdm@google.com>
  - 2888fe17796d7afa45f4b6ca7eb8e88f52739c39 StrCat: Support zero-padding and space-padding for decima... by Jorg Brown <jorg@google.com>
  - feebc521195241783730df9700394f6585550ff2 Merge GitHub PR #91. by Derek Mauro <dmauro@google.com>
  - e8164335efefb7335f407c17a16fce2ba4f24e3e This changes the value base_internal::kOnceDone from 32-b... by Abseil Team <absl-team@google.com>
  - 0f6085f3f0ee1d6baf9a558d07a25c2fcde93273 Remove `compliant` field from some type trait structs. by Matt Armstrong <marmstrong@google.com>

GitOrigin-RevId: a0405e7870a80a9dbc6784b06795e7df5a8c90f5
Change-Id: Ic2efd40f6ec35f79a8aa12d4475cbea3150756d7
diff --git a/absl/base/call_once.h b/absl/base/call_once.h
index 5d823a1..25c783e 100644
--- a/absl/base/call_once.h
+++ b/absl/base/call_once.h
@@ -134,7 +134,10 @@
   kOnceInit = 0,
   kOnceRunning = 0x65C2937B,
   kOnceWaiter = 0x05A308D2,
-  kOnceDone = 0x3F2D8AB0,
+  // A very small constant is chosen for kOnceDone so that it fit in a single
+  // compare with immediate instruction for most common ISAs.  This is verified
+  // for x86, POWER and ARM.
+  kOnceDone = 221,    // Random Number
 };
 
 template <typename Callable, typename... Args>