Reland of SkOncePtr -> SkOnce (patchset #1 id:1 of https://codereview.chromium.org/1945293004/ )

Reason for revert:
previous revert unneeded (I think)

Original issue's description:
> Revert of SkOncePtr -> SkOnce (patchset #4 id:60001 of https://codereview.chromium.org/1953533002/ )
>
> Reason for revert:
> broken the Mac and Linux builders, e.g.:
>
> https://build.chromium.org/p/chromium/builders/Mac/builds/15151
> https://build.chromium.org/p/chromium/builders/Linux%20x64/builds/19052
>
> Original issue's description:
> > SkOncePtr -> SkOnce
> >
> > It's always nice to kill off a synchronization primitive.
> > And while less terse, I think this new code reads more clearly.
> >
> > ... and, SkOncePtr's tests were the only thing now using sk_num_cores()
> > outside of SkTaskGroup, so I've hidden it as static inside SkTaskGroup.cpp.
> >
> > BUG=skia:
> > GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1953533002
> > CQ_EXTRA_TRYBOTS=client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot
> >
> > Committed: https://skia.googlesource.com/skia/+/9bd3fc7fa9bb7cad050bd619aa93d4c48ebb5c02
>
> TBR=herb@google.com,mtklein@chromium.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/7eb33da7eede34c050b865dbb1b60c3dcea7191b

TBR=herb@google.com,mtklein@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review-Url: https://codereview.chromium.org/1949313003

1 files changed, 12 insertions, 9 deletions

diff --git a/src/core/SkXfermode.cpp b/src/core/SkXfermode.cpp
index 1cfe864751..b6d23888a7 100644
--- a/src/core/SkXfermode.cpp
+++ b/src/core/SkXfermode.cpp
@@ -9,7 +9,7 @@
 #include "SkXfermode_proccoeff.h"
 #include "SkColorPriv.h"
 #include "SkMathPriv.h"
-#include "SkOncePtr.h"
+#include "SkOnce.h"
 #include "SkOpts.h"
 #include "SkReadBuffer.h"
 #include "SkString.h"
@@ -1303,11 +1303,7 @@ void SkProcCoeffXfermode::toString(SkString* str) const {
 #endif
 
 
-SK_DECLARE_STATIC_ONCE_PTR(SkXfermode, cached[SkXfermode::kLastMode + 1]);
-
 sk_sp<SkXfermode> SkXfermode::Make(Mode mode) {
-    SkASSERT(SK_ARRAY_COUNT(gProcCoeffs) == kModeCount);
-
     if ((unsigned)mode >= kModeCount) {
         // report error
         return nullptr;
@@ -1319,13 +1315,20 @@ sk_sp<SkXfermode> SkXfermode::Make(Mode mode) {
         return nullptr;
     }
 
-    return sk_ref_sp(cached[mode].get([=]{
+    SkASSERT(SK_ARRAY_COUNT(gProcCoeffs) == kModeCount);
+
+    static SkOnce        once[SkXfermode::kLastMode+1];
+    static SkXfermode* cached[SkXfermode::kLastMode+1];
+
+    once[mode]([mode] {
         ProcCoeff rec = gProcCoeffs[mode];
         if (auto xfermode = SkOpts::create_xfermode(rec, mode)) {
-            return xfermode;
+            cached[mode] = xfermode;
+        } else {
+            cached[mode] = new SkProcCoeffXfermode(rec, mode);
         }
-        return (SkXfermode*) new SkProcCoeffXfermode(rec, mode);
-    }));
+    });
+    return sk_ref_sp(cached[mode]);
 }
 
 SkXfermodeProc SkXfermode::GetProc(Mode mode) {