Fix an assertion failure in InputType::applyStep()

third_party/WebKit/Source/platform/Decimal.h

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 161 matching lines @@
     Decimal compareTo(const Decimal&) const;
 
     static AlignedOperands alignOperands(const Decimal& lhs, const Decimal& rhs);
     static inline Sign invertSign(Sign sign) { return sign == Negative ? Positive : Negative; }
 
     Sign getSign() const { return m_data.getSign(); }
 
     EncodedData m_data;
 };
 
+PLATFORM_EXPORT std::ostream& operator<<(std::ostream&, const Decimal&);
+
 } // namespace blink
 
 #endif // Decimal_h