grunt/config/bower_concat.js
function(mainFiles /*, component*/) {
                for (var i=0; i<mainFiles.length; i++ ){
                    //Use no-minified version if available
                    var parts = mainFiles[i].split('.'),
                        ext   = parts.pop(),
                        min   = parts.pop(),
                        fName;
                    if (min == 'min'){
                      parts.push(ext);
                        fName = parts.join('.');
                        if (grunt.file.exists(fName))
                            mainFiles[i] = fName;
                    }
                }
                return mainFiles;
            }
function(mainFiles /*, component*/) {
                for (var i=0; i<mainFiles.length; i++ ){
                    //Use no-minified version if available
                    var parts = mainFiles[i].split('.'),
                        ext   = parts.pop(),
                        min   = parts.pop(),
                        fName;
                    if (min == 'min'){
                      parts.push(ext);
                        fName = parts.join('.');
                        if (grunt.file.exists(fName))
                            mainFiles[i] = fName;
                    }
                }
                return mainFiles;
            }
Is set by the task "_read_overrides_and_resolutions"