SkOnce: 2 bytes -> 1 byte

include/private/SkOncePtr.h

Index: include/private/SkOncePtr.h
diff --git a/include/private/SkOncePtr.h b/include/private/SkOncePtr.h
index 3c1ab634ee4397d747cebf7fcfbfb616b189f1fb..b60d968b4a4ef7825d16c558cbaf822206f94abe 100644
--- a/include/private/SkOncePtr.h
+++ b/include/private/SkOncePtr.h
@@ -66,8 +66,9 @@ public:
             if (state == 0) {
                 // It looks like no one has tried to create our pointer yet.
                 // We try to claim that task by atomically swapping our state from '0' to '1'.
+                // See SkOnce.h for why we use an acquire memory order here rather than relaxed.
                 if (sk_atomic_compare_exchange(
-                    &fState, &state, (uintptr_t)1, sk_memory_order_relaxed, sk_memory_order_relaxed)) {
+                    &fState, &state, (uintptr_t)1, sk_memory_order_acquire, sk_memory_order_acquire)) {
                     // We've claimed it.  Create our pointer and store it into fState.
                     state = (uintptr_t)f();
                     SkASSERT(state > 1);