Remove OwnPtr from Blink.

third_party/WebKit/Source/core/animation/LengthUnitsChecker.h

Index: third_party/WebKit/Source/core/animation/LengthUnitsChecker.h
diff --git a/third_party/WebKit/Source/core/animation/LengthUnitsChecker.h b/third_party/WebKit/Source/core/animation/LengthUnitsChecker.h
index 65570c489bd4e26a947c56f9d7b54497300560e5..67fbe708848c7e03ce70de4d1d4679e9ee48908f 100644
--- a/third_party/WebKit/Source/core/animation/LengthUnitsChecker.h
+++ b/third_party/WebKit/Source/core/animation/LengthUnitsChecker.h
@@ -8,12 +8,14 @@
 #include "core/animation/InterpolationType.h"
 #include "core/css/CSSPrimitiveValue.h"
 #include "core/css/resolver/StyleResolverState.h"
+#include "wtf/PtrUtil.h"
+#include <memory>
 
 namespace blink {
 
 class LengthUnitsChecker : public InterpolationType::ConversionChecker {
 public:
-    static PassOwnPtr<LengthUnitsChecker> maybeCreate(CSSLengthArray&& lengthArray, const StyleResolverState& state)
+    static std::unique_ptr<LengthUnitsChecker> maybeCreate(CSSLengthArray&& lengthArray, const StyleResolverState& state)
     {
         bool create = false;
         size_t lastIndex = 0;
@@ -26,7 +28,7 @@ public:
         }
         if (!create)
             return nullptr;
-        return adoptPtr(new LengthUnitsChecker(std::move(lengthArray), lastIndex));
+        return wrapUnique(new LengthUnitsChecker(std::move(lengthArray), lastIndex));
     }
 
     bool isValid(const InterpolationEnvironment& environment, const InterpolationValue& underlying) const final