function deprecationWarning(identifier, message) {
  //>>includeStart('debug', pragmas.debug);
  if (!defined(identifier) || !defined(message)) {
    throw new DeveloperError("identifier and message are required.");
  }
  //>>includeEnd('debug');

  oneTimeWarning(identifier, message);
}
Logs a deprecation message to the console.  Use this function instead of
<code>console.log</code> directly since this does not log duplicate messages
unless it is called from multiple workers.

@function deprecationWarning

@param {string} identifier The unique identifier for this deprecated API.
@param {string} message The message to log to the console.

@example
// Deprecated function or class
function Foo() {
   deprecationWarning('Foo', 'Foo was deprecated in Cesium 1.01.  It will be removed in 1.03.  Use newFoo instead.');
   // ...
}

// Deprecated function
Bar.prototype.func = function() {
   deprecationWarning('Bar.func', 'Bar.func() was deprecated in Cesium 1.01.  It will be removed in 1.03.  Use Bar.newFunc() instead.');
   // ...
};

// Deprecated property
Object.defineProperties(Bar.prototype, {
    prop : {
        get : function() {
            deprecationWarning('Bar.prop', 'Bar.prop was deprecated in Cesium 1.01.  It will be removed in 1.03.  Use Bar.newProp instead.');
            // ...
        },
        set : function(value) {
            deprecationWarning('Bar.prop', 'Bar.prop was deprecated in Cesium 1.01.  It will be removed in 1.03.  Use Bar.newProp instead.');
            // ...
        }
    }
});

@private