Remove OwnPtr from Blink.

third_party/WebKit/Source/core/editing/EditingTestBase.h

Index: third_party/WebKit/Source/core/editing/EditingTestBase.h
diff --git a/third_party/WebKit/Source/core/editing/EditingTestBase.h b/third_party/WebKit/Source/core/editing/EditingTestBase.h
index 1f30bac7763f3ad9312033591f5b869bfc70a6af..53f971bac2d26b1b52d87598b019974a0a0b6fef 100644
--- a/third_party/WebKit/Source/core/editing/EditingTestBase.h
+++ b/third_party/WebKit/Source/core/editing/EditingTestBase.h
@@ -8,6 +8,7 @@
 #include "core/editing/Position.h"
 #include "wtf/Forward.h"
 #include <gtest/gtest.h>
+#include <memory>
 #include <string>
 
 namespace blink {
@@ -32,7 +33,7 @@ protected:
     void updateAllLifecyclePhases();
 
 private:
-    OwnPtr<DummyPageHolder> m_dummyPageHolder;
+    std::unique_ptr<DummyPageHolder> m_dummyPageHolder;
 };
 
 } // namespace blink