Use nullptr_t for RefPtr, PassRefPtr and RawPtr.

Source/modules/indexeddb/IDBRequestTest.cpp

Index: Source/modules/indexeddb/IDBRequestTest.cpp
diff --git a/Source/modules/indexeddb/IDBRequestTest.cpp b/Source/modules/indexeddb/IDBRequestTest.cpp
index a63a5fc9b823bb81cdd82d806511543cff082893..3dc1bf24d5daec2ac5d70d064abc544c968e7854 100644
--- a/Source/modules/indexeddb/IDBRequestTest.cpp
+++ b/Source/modules/indexeddb/IDBRequestTest.cpp
@@ -99,13 +99,13 @@ TEST_F(IDBRequestTest, EventsAfterStopping)
     // Ensure none of the following raise assertions in stopped state:
     request->onError(DOMError::create(AbortError, "Description goes here."));
     request->onSuccess(Vector<String>());
-    request->onSuccess(nullptr, IDBKey::createInvalid(), IDBKey::createInvalid(), 0);
+    request->onSuccess(nullptr, IDBKey::createInvalid(), IDBKey::createInvalid(), nullptr);
     request->onSuccess(IDBKey::createInvalid());
-    request->onSuccess(PassRefPtr<SharedBuffer>(0));
-    request->onSuccess(PassRefPtr<SharedBuffer>(0), IDBKey::createInvalid(), IDBKeyPath());
+    request->onSuccess(PassRefPtr<SharedBuffer>(nullptr));
+    request->onSuccess(PassRefPtr<SharedBuffer>(nullptr), IDBKey::createInvalid(), IDBKeyPath());
     request->onSuccess(0LL);
     request->onSuccess();
-    request->onSuccess(IDBKey::createInvalid(), IDBKey::createInvalid(), 0);
+    request->onSuccess(IDBKey::createInvalid(), IDBKey::createInvalid(), nullptr);
 }
 
 TEST_F(IDBRequestTest, AbortErrorAfterAbort)