The throng of people, police and television camera crews at the other end of Quiana Johnson’s west Baltimore street Friday morning meant only one thing to the 14-year-old: trouble.“What’s the problem over there?” Johnson asked in a low voice, her head poking out of the front door of her family’s red brick row home, past the burned-out house next door and the other vacant, boarded-up homes on the 600 block of West Lafayette Street.Actually, the crowd of about 80 people were dignitaries, media and community leaders gathered for the rededication of a statue of internationally-famous jazz singer Billie Holiday, who grew up in Baltimore and returned here to perform. To say the event was joyous, however, or somehow the opposite of what Quiana imagined, would not be quite right. Call it bittersweet.