Remove IgnorableExceptionState

third_party/WebKit/Source/bindings/core/v8/ExceptionState.h

 /*
  * Copyright (C) 2013 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 169 matching lines @@
       : ExceptionState(nullptr,
                        ExceptionState::UnknownContext,
                        nullptr,
                        nullptr) {}
   ~DummyExceptionStateForTesting() {
     // Prevent the base class throw an exception.
     if (hadException()) {
       clearException();
     }
   }
-
   void throwDOMException(ExceptionCode, const String& message) override;
   void throwTypeError(const String& message) override;
   void throwSecurityError(const String& sanitizedMessage,
                           const String& unsanitizedMessage) override;
   void throwRangeError(const String& message) override;
   void rethrowV8Exception(v8::Local<v8::Value>) override;
+  ExceptionState& returnThis() { return *this; }
 };
 
 }  // namespace blink
 
 #endif  // ExceptionState_h