Rename DatabaseTaskSynchronizer to TaskSynchronizer and move it to platform/

Source/platform/TaskSynchronizer.cpp

Index: Source/platform/TaskSynchronizer.cpp
diff --git a/Source/core/accessibility/AXSVGRoot.cpp b/Source/platform/TaskSynchronizer.cpp
similarity index 66%
copy from Source/core/accessibility/AXSVGRoot.cpp
copy to Source/platform/TaskSynchronizer.cpp
index 7c2efa2cc2e7149c76eef89f21f5e3a3d61f57e0..af8be01b7ad8604050131512dbe892bd68faf118 100644
--- a/Source/core/accessibility/AXSVGRoot.cpp
+++ b/Source/platform/TaskSynchronizer.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012 Apple Inc. All rights reserved.
+ * Copyright (C) 2007, 2008, 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
@@ -27,35 +27,37 @@
  */
 
 #include "config.h"
-#include "core/accessibility/AXSVGRoot.h"
+#include "platform/TaskSynchronizer.h"
 
+#include "heap/ThreadState.h"
 
 namespace WebCore {
 
-AXSVGRoot::AXSVGRoot(RenderObject* renderer)
-    : AXRenderObject(renderer)
-    , m_parent(0)
+TaskSynchronizer::TaskSynchronizer()
+    : m_taskCompleted(false)
+#ifndef NDEBUG
+    , m_hasCheckedForTermination(false)
+#endif
 {
 }
 
-AXSVGRoot::~AXSVGRoot()
+void TaskSynchronizer::waitForTaskCompletion()
 {
+    // Prevent the deadlock between park request by other threads and blocking
+    // by m_synchronousCondition.
+    ThreadState::SafePointScope scope(ThreadState::HeapPointersOnStack);
+    m_synchronousMutex.lock();
+    while (!m_taskCompleted)
+        m_synchronousCondition.wait(m_synchronousMutex);
+    m_synchronousMutex.unlock();
 }
 
-PassRefPtr<AXSVGRoot> AXSVGRoot::create(RenderObject* renderer)
+void TaskSynchronizer::taskCompleted()
 {
-    return adoptRef(new AXSVGRoot(renderer));
+    m_synchronousMutex.lock();
+    m_taskCompleted = true;
+    m_synchronousCondition.signal();
+    m_synchronousMutex.unlock();
 }
 
-AXObject* AXSVGRoot::parentObject() const
-{
-    // If a parent was set because this is a remote SVG resource, use that
-    // but otherwise, we should rely on the standard render tree for the parent.
-    if (m_parent)
-        return m_parent;
-
-    return AXRenderObject::parentObject();
-}
-
-
 } // namespace WebCore