Rename DatabaseTaskSynchronizer to TaskSynchronizer and move it to platform/

Source/platform/TaskSynchronizer.h

Index: Source/platform/TaskSynchronizer.h
diff --git a/Source/platform/text/StringTruncator.h b/Source/platform/TaskSynchronizer.h
similarity index 63%
copy from Source/platform/text/StringTruncator.h
copy to Source/platform/TaskSynchronizer.h
index a1aff51fe4eec987443f9424884cf1f9ab6915aa..71fd44a525d6cc5c562566ac7bc1fba669aed2e1 100644
--- a/Source/platform/text/StringTruncator.h
+++ b/Source/platform/TaskSynchronizer.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2005, 2006, 2007 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
@@ -26,25 +26,41 @@
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef StringTruncator_h
-#define StringTruncator_h
+#ifndef TaskSynchronizer_h
+#define TaskSynchronizer_h
 
-#include "platform/PlatformExport.h"
-#include "wtf/Forward.h"
+#include "wtf/Noncopyable.h"
+#include "wtf/Threading.h"
+#include "wtf/ThreadingPrimitives.h"
 
 namespace WebCore {
 
-class Font;
-
-class PLATFORM_EXPORT StringTruncator {
+// TaskSynchronizer can be used to wait for task completion.
+class TaskSynchronizer {
+    WTF_MAKE_NONCOPYABLE(TaskSynchronizer);
 public:
-    enum EnableRoundingHacksOrNot { DisableRoundingHacks, EnableRoundingHacks };
+    TaskSynchronizer();
+
+    // Called from a thread that waits for the task completion.
+    void waitForTaskCompletion();
+
+    // Called from a thread that executes the task.
+    void taskCompleted();
+
+#ifndef NDEBUG
+    bool hasCheckedForTermination() const { return m_hasCheckedForTermination; }
+    void setHasCheckedForTermination() { m_hasCheckedForTermination = true; }
+#endif
 
-    static String centerTruncate(const String&, float maxWidth, const Font&, EnableRoundingHacksOrNot = DisableRoundingHacks);
-    static String rightTruncate(const String&, float maxWidth, const Font&, EnableRoundingHacksOrNot = DisableRoundingHacks);
-    static float width(const String&, const Font&, EnableRoundingHacksOrNot = DisableRoundingHacks);
+private:
+    bool m_taskCompleted;
+    Mutex m_synchronousMutex;
+    ThreadCondition m_synchronousCondition;
+#ifndef NDEBUG
+    bool m_hasCheckedForTermination;
+#endif
 };
 
-} // namespace WebCore
+}
 
-#endif // !defined(StringTruncator_h)
+#endif // TaskSynchronizer_h