B2G/gecko/browser/devtools/styleinspector/CssRuleView.jsm
/**
   * Get a named property for a given CSSStyleDeclaration.
   *
   * @param {CSSStyleDeclaration} aStyle
   *        The CSSStyleDeclaration against which the property is mapped.
   * @param {String} aName
   *        The name of the property to get.
   * @param {String} aComputedValue
   *        The computed value of the property.  The user value will only be
   *        returned if the computed value hasn't changed since, and this will
   *        be returned as the default if no user value is available.
   * @returns {String}
   *          The property value if it has previously been set by the user, null
   *          otherwise.
   */
Get a named property for a given CSSStyleDeclaration.
@param {CSSStyleDeclaration} aStyle
The CSSStyleDeclaration against which the property is mapped.
@param {String} aName
The name of the property to get.
@param {String} aComputedValue
The computed value of the property.  The user value will only be
returned if the computed value hasn't changed since, and this will
be returned as the default if no user value is available.
@returns {String}
The property value if it has previously been set by the user, null
otherwise.
Get a named property for a given CSSStyleDeclaration . @param { CSSStyleDeclaration } aStyle The CSSStyleDeclaration against which the property is mapped . @param { String } aName The name of the property to get . @param { String } aComputedValue The computed value of the property . The user value will only be returned if the computed value hasn ' t changed since and this will be returned as the default if no user value is available . @returns { String } The property value if it has previously been set by the user null otherwise .
function UP_getProperty(aStyle, aName, aComputedValue) {
    let entry = this.map.get(aStyle, null);
    if (entry && aName in entry) {
      let item = entry[aName];
      if (item.computed != aComputedValue) {
        delete entry[aName];
        return aComputedValue;
      }
      return item.user;
    }
    return aComputedValue;
  }
function UP_getProperty ( aStyle , aName , aComputedValue ) { let entry = this . map . get ( aStyle , null ) ; if ( entry && aName in entry ) { let item = entry [ aName ] ; if ( item . computed != aComputedValue ) { delete entry [ aName ] ; return aComputedValue ; } return item . user ; } return aComputedValue ; }
Get a named property for a given CSSStyleDeclaration.
Get a named property for a given CSSStyleDeclaration .