Is it possible? There is no mention of content-aware fill in JS Scripting reference 5 + 6.
When there is nothing in the scripting guides think of the scritlistener plugin and the action manager code it records,
// =======================================================
var idFl = charIDToTypeID( "Fl " );
var desc12 = new ActionDescriptor();
var idUsng = charIDToTypeID( "Usng" );
var idFlCn = charIDToTypeID( "FlCn" );
var idcontentAware = stringIDToTypeID( "contentAware" );
desc12.putEnumerated( idUsng, idFlCn, idcontentAware );
var idOpct = charIDToTypeID( "Opct" );
var idPrc = charIDToTypeID( "#Prc" );
desc12.putUnitDouble( idOpct, idPrc, 100.000000 );
var idMd = charIDToTypeID( "Md " );
var idBlnM = charIDToTypeID( "BlnM" );
var idNrml = charIDToTypeID( "Nrml" );
desc12.putEnumerated( idMd, idBlnM, idNrml );
executeAction( idFl, desc12, DialogModes.NO );
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