[PPAPI] Fix a bunch of spelling mistakes

ppapi/cpp/dev/scriptable_object_deprecated.h

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef PPAPI_CPP_SCRIPTABLE_OBJECT_DEPRECATED_H_
 #define PPAPI_CPP_SCRIPTABLE_OBJECT_DEPRECATED_H_
 
 #include <vector>
 
 struct PPP_Class_Deprecated;
@@ skipping 62 matching lines @@
   // The default implementation sets an exception that the method does not
   // exist.
   virtual Var Construct(const std::vector<Var>& args,
                         Var* exception);
 
  private:
   friend class ::pp::Var;
   friend class ::pp::VarPrivate;
   static const PPP_Class_Deprecated* GetClass();
 
-  // Unimplemented, copy and assigmnent is not allowed.
+  // Unimplemented, copy and assignment is not allowed.
   ScriptableObject(const ScriptableObject& other);
   ScriptableObject& operator=(const ScriptableObject& other);
 };
 
 }  // namespace deprecated
 
 }  // namespace pp
 
 #endif  // PPAPI_CPP_SCRIPTABLE_OBJECT_DEPRECATED_H_