Avoid large inlined automatic methods in IndexedDB code.

content/common/indexed_db/indexed_db_key_path.cc

Index: content/common/indexed_db/indexed_db_key_path.cc
diff --git a/content/common/indexed_db/indexed_db_key_path.cc b/content/common/indexed_db/indexed_db_key_path.cc
index 3783d4281a8fc7090e3a9645fc99e24dc10036cc..a5756b5141806ced7639f65ca62146be10a46dc5 100644
--- a/content/common/indexed_db/indexed_db_key_path.cc
+++ b/content/common/indexed_db/indexed_db_key_path.cc
@@ -20,7 +20,10 @@ IndexedDBKeyPath::IndexedDBKeyPath(const base::string16& string)
 IndexedDBKeyPath::IndexedDBKeyPath(const std::vector<base::string16>& array)
     : type_(WebIDBKeyPathTypeArray), array_(array) {}
 
-IndexedDBKeyPath::~IndexedDBKeyPath() {}
+IndexedDBKeyPath::IndexedDBKeyPath(const IndexedDBKeyPath& other) = default;
+IndexedDBKeyPath::~IndexedDBKeyPath() = default;
+IndexedDBKeyPath& IndexedDBKeyPath::operator=(const IndexedDBKeyPath& other) =
+    default;
 
 const std::vector<base::string16>& IndexedDBKeyPath::array() const {
   DCHECK(type_ == blink::WebIDBKeyPathTypeArray);