Reland of SkOncePtr -> SkOnce

src/core/SkColorSpace.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkAtomics.h"
 #include "SkColorSpace.h"
-#include "SkOncePtr.h"
+#include "SkOnce.h"
 
 static bool color_space_almost_equal(float a, float b) {
     return SkTAbs(a - b) < 0.01f;
 }
 
 void SkFloat3::dump() const {
     SkDebugf("[%7.4f %7.4f %7.4f]\n", fVec[0], fVec[1], fVec[2]);
 }
 
 //////////////////////////////////////////////////////////////////////////////////////////////////
@@ skipping 15 matching lines @@
     , fUniqueID(sk_atomic_inc(&gUniqueColorSpaceID))
     , fNamed(kUnknown_Named)
 {}
 
 const float gSRGB_toXYZD50[] {
     0.4358f, 0.2224f, 0.0139f,    // * R
     0.3853f, 0.7170f, 0.0971f,    // * G
     0.1430f, 0.0606f, 0.7139f,    // * B
 };
 
-SK_DECLARE_STATIC_ONCE_PTR(SkColorSpace, sRGB);
-
 sk_sp<SkColorSpace> SkColorSpace::NewRGB(SkGammas gammas, const SkMatrix44& toXYZD50) {
     // Check if we really have sRGB
     if (color_space_almost_equal(2.2f, gammas.fRed.fValue) &&
         color_space_almost_equal(2.2f, gammas.fGreen.fValue) &&
         color_space_almost_equal(2.2f, gammas.fBlue.fValue) &&
         color_space_almost_equal(toXYZD50.getFloat(0, 0), gSRGB_toXYZD50[0]) &&
         color_space_almost_equal(toXYZD50.getFloat(0, 1), gSRGB_toXYZD50[1]) &&
         color_space_almost_equal(toXYZD50.getFloat(0, 2), gSRGB_toXYZD50[2]) &&
         color_space_almost_equal(toXYZD50.getFloat(1, 0), gSRGB_toXYZD50[3]) &&
         color_space_almost_equal(toXYZD50.getFloat(1, 1), gSRGB_toXYZD50[4]) &&
         color_space_almost_equal(toXYZD50.getFloat(1, 2), gSRGB_toXYZD50[5]) &&
         color_space_almost_equal(toXYZD50.getFloat(2, 0), gSRGB_toXYZD50[6]) &&
         color_space_almost_equal(toXYZD50.getFloat(2, 1), gSRGB_toXYZD50[7]) &&
         color_space_almost_equal(toXYZD50.getFloat(2, 2), gSRGB_toXYZD50[8]) &&
         color_space_almost_equal(toXYZD50.getFloat(0, 3), 0.0f) &&
         color_space_almost_equal(toXYZD50.getFloat(1, 3), 0.0f) &&
         color_space_almost_equal(toXYZD50.getFloat(2, 3), 0.0f) &&
         color_space_almost_equal(toXYZD50.getFloat(3, 0), 0.0f) &&
         color_space_almost_equal(toXYZD50.getFloat(3, 1), 0.0f) &&
         color_space_almost_equal(toXYZD50.getFloat(3, 2), 0.0f) &&
         color_space_almost_equal(toXYZD50.getFloat(3, 3), 1.0f))
     {
         return SkColorSpace::NewNamed(kSRGB_Named);
     }
 
     return sk_sp<SkColorSpace>(new SkColorSpace(std::move(gammas), toXYZD50, kUnknown_Named));
 }
 
 sk_sp<SkColorSpace> SkColorSpace::NewNamed(Named named) {
+    static SkOnce once;
+    static SkColorSpace* sRGB;
+
     switch (named) {
         case kSRGB_Named: {
-            SkMatrix44 srgbToxyzD50(SkMatrix44::kUninitialized_Constructor);
-            srgbToxyzD50.set3x3ColMajorf(gSRGB_toXYZD50);
-            return sk_ref_sp(sRGB.get([=]{
-                return new SkColorSpace(SkGammas(2.2f, 2.2f, 2.2f), srgbToxyzD50, kSRGB_Named);
-            }));
+            once([] {
+                SkMatrix44 srgbToxyzD50(SkMatrix44::kUninitialized_Constructor);
+                srgbToxyzD50.set3x3ColMajorf(gSRGB_toXYZD50);
+                sRGB = new SkColorSpace(SkGammas(2.2f, 2.2f, 2.2f), srgbToxyzD50, kSRGB_Named);
+            });
+            return sk_ref_sp(sRGB);
         }
         default:
             break;
     }
     return nullptr;
 }
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 #include "SkFixed.h"
@@ skipping 538 matching lines @@
                                                             toXYZ));
             }
 
         }
         default:
             break;
     }
 
     return_null("ICC profile contains unsupported colorspace");
 }