Bug 70929

Section 4.5.5 of the Web IDL, http://www.w3.org/TR/WebIDL/#es-attributes, states that "For each attribute defined on the interface, there must exist a corresponding property. If the attribute was declared with the [Unforgeable] extended attribute, then the property exists on every object that implements the interface. Otherwise, it exists on the interface’s interface prototype object." WebKit, however, appears to define these as instance properties. This introduces several incompatibilities, such as checking own properties or getting property descriptors. For a specific example, In WebKit and Presto: > document.body.hasOwnProperty("style") // -> true In Trident and Gecko: > document.body.hasOwnProperty("style") // -> false