Avoid leaking ThreadingPrimitives.h from StackStats.h when collection is off.

Source/wtf/StackStats.h

Index: Source/wtf/StackStats.h
diff --git a/Source/wtf/StackStats.h b/Source/wtf/StackStats.h
deleted file mode 100644
index c0c424c4d86de33d3187a74d768c5b96d54e49df..0000000000000000000000000000000000000000
--- a/Source/wtf/StackStats.h
+++ /dev/null
@@ -1,150 +0,0 @@
-/*
- * Copyright (C) 2012 Apple Inc. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
- * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
- * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
- * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
- * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
- * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef StackStats_h
-#define StackStats_h
-
-#include "ThreadingPrimitives.h"
-
-
-// Define this flag to enable Stack stats collection. This feature is useful
-// for getting a sample of native stack usage sizes.
-//
-// Enabling this will cause stats to be collected and written to a log file at
-// various  instrumented points in the code. It will result in noticeable
-// performance loss. Hence, this should only be enable when you want to do
-// some stats location in your local build. This code is provided here as a
-// convenience for collecting that data. It is not meant to be enabled by
-// default on release or debug builds.
-
-// #define ENABLE_STACK_STATS 1
-
-
-namespace WTF {
-
-#if !ENABLE(STACK_STATS)
-
-class StackStats {
-public:
-    // The CheckPoint class is for marking check points corresponding
-    // each location in code where a stack recursion check is being done.
-
-    class CheckPoint {
-    public:
-        CheckPoint() { }
-    };
-
-    class PerThreadStats {
-    public:
-        PerThreadStats() { }
-    };
-
-    class LayoutCheckPoint {
-    public:
-        LayoutCheckPoint() { }
-    };
-
-    static void initialize() { }
-    static void probe() { }
-};
-
-#else // ENABLE(STACK_STATS)
-
-class StackStats {
-public:
-    // The CheckPoint class is for marking check points corresponding
-    // each location in code where a stack recursion check is being done.
-
-    class CheckPoint {
-    public:
-        CheckPoint();
-        ~CheckPoint();
-    private:
-        CheckPoint* m_prev;
-    };
-
-    class PerThreadStats {
-    public:
-        PerThreadStats();
-
-    private:
-        int m_reentryDepth;
-        char* m_stackStart;
-        CheckPoint* m_currentCheckPoint;
-
-        friend class CheckPoint;
-        friend class StackStats;
-    };
-
-    class LayoutCheckPoint {
-    public:
-        LayoutCheckPoint();
-        ~LayoutCheckPoint();
-
-    private:
-        LayoutCheckPoint* m_prev;
-        int m_depth;
-    };
-
-    // Initializes locks and the log file. Should only be called once.
-    static void initialize();
-
-    // Used for probing the stack at places where we suspect to be high
-    // points of stack usage but are NOT check points where stack recursion
-    // is checked.
-    //
-    // The more places where we add this probe, the more accurate our
-    // stats data will be. However, adding too many probes will also
-    // result in unnecessary performance loss. So, only add these probes
-    // judiciously where appropriate.
-    static void probe();
-
-private:
-    // CheckPoint management:
-    static Mutex* s_sharedLock;
-    static CheckPoint* s_topCheckPoint;
-    static LayoutCheckPoint* s_firstLayoutCheckPoint;
-    static LayoutCheckPoint* s_topLayoutCheckPoint;
-
-    // High watermark stats:
-    static int s_maxCheckPointDiff;
-    static int s_maxStackHeight;
-    static int s_maxReentryDepth;
-
-    static int s_maxLayoutCheckPointDiff;
-    static int s_maxTotalLayoutCheckPointDiff;
-    static int s_maxLayoutReentryDepth;
-
-    friend class CheckPoint;
-    friend class LayoutCheckPoint;
-};
-
-#endif // ENABLE(STACK_STATS)
-
-} // namespace WTF
-
-using WTF::StackStats;
-
-#endif // StackStats_h