Mexican orange (Choisya ternata).
Mexican orange is a small and compact evergreen broadleaf shrub that gets about 6-8 ft (1.8-2.4 m) tall. It is a tropical shrub growing in USDA zone 8-10. Mexican orange is very showy, especially during its blooming period which lasts several weeks from early spring to summer.
If you want more information about this flower, just search the plant's Latin name on Google: