Restore AutodrainedPoolMac.mm, use it in blink/mac.

Source/WTF/wtf/AutodrainedPoolMac.mm

Index: Source/WTF/wtf/AutodrainedPoolMac.mm
diff --git a/Source/WTF/wtf/Complex.h b/Source/WTF/wtf/AutodrainedPoolMac.mm
similarity index 73%
copy from Source/WTF/wtf/Complex.h
copy to Source/WTF/wtf/AutodrainedPoolMac.mm
index 40fe56a7bb75442efae4d589cf4970fcffee56f9..1c7f182ee068ecfbe3eb5ad01b87a8f407c11a5c 100644
--- a/Source/WTF/wtf/Complex.h
+++ b/Source/WTF/wtf/AutodrainedPoolMac.mm
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2010 Google Inc. All rights reserved.
+ * Copyright (C) 2007, 2013 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -26,24 +26,32 @@
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef WTF_Complex_h
-#define WTF_Complex_h
+#import "config.h"
+#import "AutodrainedPool.h"
 
-#include <complex>
-#include <wtf/MathExtras.h>
+#import <Foundation/Foundation.h>
 
 namespace WTF {
 
-typedef std::complex<double> Complex;
-
-inline Complex complexFromMagnitudePhase(double magnitude, double phase)
+AutodrainedPool::AutodrainedPool(int iterationLimit)
+    : m_iterationLimit(iterationLimit)
+    , m_iterationCount(0)
+    , m_pool([[NSAutoreleasePool alloc] init])
 {
-    return Complex(magnitude * cos(phase), magnitude * sin(phase));
 }
 
-} // namespace WTF
+AutodrainedPool::~AutodrainedPool()
+{
+    [m_pool drain];
+}
 
-using WTF::Complex;
-using WTF::complexFromMagnitudePhase;
+void AutodrainedPool::cycle()
+{
+    if (++m_iterationCount == m_iterationLimit) {
+        [m_pool drain];
+        m_pool = [[NSAutoreleasePool alloc] init];
+        m_iterationCount = 0;
+    }
+}
 
-#endif // WTF_Complex_h
+} // namespace WTF