Unsets the feature of the object.
If the feature is {@link ETypedElement#isMany() many-valued}, the value must be an {@link EList}and that list is cleared. Otherwise, the value of the feature of the object is set to the feature's {@link EStructuralFeature#getDefaultValue() default value}or the {@link #eClass meta class}'s {@link EStructuralFeature#getDefaultValue() default value}, as appropriate. If the feature is {@link EStructuralFeature#isUnsettable() unsettable}, the modeled state becomes unset. In any case, the feature will no longer be considered {@link #eIsSet set}.
@param feature the feature in question.
@exception IllegalArgumentException if the feature is not one the {@link #eClass meta class}'s {@link EClass#getEAllStructuralFeatures features}, or it isn't {@link EStructuralFeature#isChangeable changeable}.
@see #eIsSet(EStructuralFeature)
@see #eSet(EStructuralFeature,Object)
@see #eGet(EStructuralFeature,boolean)
@ignore
@model
@generated