Port most uses of SkOnce to SkLazyPtr.

src/core/SkFontHost.cpp

 /*
  * Copyright 2009 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkFontLCDConfig.h"
-#include "SkOnce.h"
+#include "SkLazyPtr.h"
 
 static SkFontLCDConfig::LCDOrientation gLCDOrientation = SkFontLCDConfig::kHorizontal_LCDOrientation;
 static SkFontLCDConfig::LCDOrder gLCDOrder = SkFontLCDConfig::kRGB_LCDOrder;
 
 SkFontLCDConfig::LCDOrientation SkFontLCDConfig::GetSubpixelOrientation() {
     return gLCDOrientation;
 }
 
 void SkFontLCDConfig::SetSubpixelOrientation(LCDOrientation orientation) {
     gLCDOrientation = orientation;
@@ skipping 171 matching lines @@
         return NULL;
     }
     return this->onCreateFromFile(path, ttcIndex);
 }
 
 SkTypeface* SkFontMgr::legacyCreateTypeface(const char familyName[],
                                             unsigned styleBits) const {
     return this->onLegacyCreateTypeface(familyName, styleBits);
 }
 
-void set_up_default(SkFontMgr** singleton) {
-  *singleton = SkFontMgr::Factory();
-  // we never want to return NULL
-  if (NULL == *singleton) {
-      *singleton = SkNEW(SkEmptyFontMgr);
-  }
+SkFontMgr* SkFontMgr::CreateDefault() {
+    SkFontMgr* fm = SkFontMgr::Factory();
+    return fm ? fm : SkNEW(SkEmptyFontMgr);
 }
 
 SkFontMgr* SkFontMgr::RefDefault() {
-    static SkFontMgr* gFM = NULL;
-    SK_DECLARE_STATIC_ONCE(once);
-    SkOnce(&once, set_up_default, &gFM);
-    return SkRef(gFM);
+    SK_DECLARE_STATIC_LAZY_PTR(SkFontMgr, singleton, CreateDefault);
+    return SkRef(singleton.get());
 }
 
 //////////////////////////////////////////////////////////////////////////
 
 #ifndef SK_FONTHOST_DOES_NOT_USE_FONTMGR
 
 #if 0
 static SkFontStyle TypefaceStyleBitsToFontStyle(SkTypeface::Style styleBits) {
     SkFontStyle::Weight weight = (styleBits & SkTypeface::kBold) ?
                                      SkFontStyle::kBold_Weight :
@@ skipping 28 matching lines @@
     SkAutoTUnref<SkFontMgr> fm(SkFontMgr::RefDefault());
     return fm->createFromFile(path);
 }
 
 SkTypeface* SkFontHost::CreateTypefaceFromStream(SkStream* stream) {
     SkAutoTUnref<SkFontMgr> fm(SkFontMgr::RefDefault());
     return fm->createFromStream(stream);
 }
 
 #endif