Revert of SkOncePtr -> SkOnce

src/core/SkTaskGroup.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkOnce.h"
 #include "SkSemaphore.h"
 #include "SkSpinlock.h"
 #include "SkTArray.h"
 #include "SkTDArray.h"
 #include "SkTaskGroup.h"
 #include "SkThreadUtils.h"
 
 #if defined(SK_BUILD_FOR_WIN32)
-    static void query_num_cores(int* cores) {
+    static void query_num_cores(int* num_cores) {
         SYSTEM_INFO sysinfo;
         GetNativeSystemInfo(&sysinfo);
-        *cores = sysinfo.dwNumberOfProcessors;
+        *num_cores = sysinfo.dwNumberOfProcessors;
     }
 #else
     #include <unistd.h>
-    static void query_num_cores(int* cores) {
-        *cores = (int)sysconf(_SC_NPROCESSORS_ONLN);
+    static void query_num_cores(int* num_cores) {
+        *num_cores = (int)sysconf(_SC_NPROCESSORS_ONLN);
     }
 #endif
 
-static int num_cores() {
-    // We cache num_cores() so we only query the OS once.
-    static int cores = 0;
+int sk_num_cores() {
+    // We cache sk_num_cores() so we only query the OS once.
+    static int num_cores = 0;
     static SkOnce once;
-    once(query_num_cores, &cores);
-    SkASSERT(cores > 0);
-    return cores;
+    once(query_num_cores, &num_cores);
+    SkASSERT(num_cores > 0);
+    return num_cores;
 }
 
 namespace {
 
 class ThreadPool : SkNoncopyable {
 public:
     static void Add(std::function<void(void)> fn, SkAtomic<int32_t>* pending) {
         if (!gGlobal) {
             return fn();
         }
@@ skipping 45 matching lines @@
         SkSpinlock* fLock;
     };
 
     struct Work {
         std::function<void(void)> fn; // A function to call
         SkAtomic<int32_t>* pending;   // then decrement pending afterwards.
     };
 
     explicit ThreadPool(int threads) {
         if (threads == -1) {
-            threads = num_cores();
+            threads = sk_num_cores();
         }
         for (int i = 0; i < threads; i++) {
             fThreads.push(new SkThread(&ThreadPool::Loop, this));
             fThreads.top()->start();
         }
     }
 
     ~ThreadPool() {
         SkASSERT(fWork.empty());  // All SkTaskGroups should be destroyed by now.
 
@@ skipping 88 matching lines @@
 
 SkTaskGroup::Enabler::~Enabler() { delete ThreadPool::gGlobal; }
 
 SkTaskGroup::SkTaskGroup() : fPending(0) {}
 
 void SkTaskGroup::wait()                            { ThreadPool::Wait(&fPending); }
 void SkTaskGroup::add(std::function<void(void)> fn) { ThreadPool::Add(fn, &fPending); }
 void SkTaskGroup::batch(int N, std::function<void(int)> fn) {
     ThreadPool::Batch(N, fn, &fPending);
 }