Change WTF::TemporaryChange to be an alias for AutoReset

third_party/WebKit/Source/wtf/TemporaryChange.h

Index: third_party/WebKit/Source/wtf/TemporaryChange.h
diff --git a/third_party/WebKit/Source/wtf/TemporaryChange.h b/third_party/WebKit/Source/wtf/TemporaryChange.h
index a0ab5b154e210d29035baf84e1c9f4ec1a7cb72b..e6d7150bf62935d26849e6ae74932b262ed96d4b 100644
--- a/third_party/WebKit/Source/wtf/TemporaryChange.h
+++ b/third_party/WebKit/Source/wtf/TemporaryChange.h
@@ -26,40 +26,14 @@
 #ifndef TemporaryChange_h
 #define TemporaryChange_h
 
-#include "wtf/Noncopyable.h"
+#include "base/auto_reset.h"
 
 namespace WTF {
 
-// TemporaryChange<> is useful for setting a variable to a new value only within a
-// particular scope. An TemporaryChange<> object changes a variable to its original
-// value upon destruction, making it an alternative to writing "var = false;"
-// or "var = oldVal;" at all of a block's exit points.
-//
-// This should be obvious, but note that an TemporaryChange<> instance should have a
-// shorter lifetime than its scopedVariable, to prevent invalid memory writes
-// when the TemporaryChange<> object is destroyed.
+// WTF::TemporaryChange is base::AutoReset. See base/auto_reset.h for documentation.
 
-template<typename T>
-class TemporaryChange {
-    WTF_MAKE_NONCOPYABLE(TemporaryChange);
-public:
-    TemporaryChange(T& scopedVariable, T newValue)
-        : m_scopedVariable(scopedVariable)
-        , m_originalValue(scopedVariable)
-    {
-        m_scopedVariable = newValue;
-    }
-
-    ~TemporaryChange()
-    {
-        m_scopedVariable = m_originalValue;
-    }
-
-
-private:
-    T& m_scopedVariable;
-    T m_originalValue;
-};
+template <typename T>
+using TemporaryChange = typename base::AutoReset<T>;

[Yuta Kitamura, 2016/07/15 03:04:41]

A compiler in my brain tells this "typename" is unnecessary. But it comes
with no guarantee ;)

[jsbell, 2016/07/18 18:42:37]

Copy/pasta. Will remove.

 
 } // namespace WTF