The police chief was grilling hot dogs and the mayor was planting trees. A community services officer was blowing bubbles and firefighters were handing out plastic fire helmets to the kids. A five-foot high cinderblock wall at the end of cul-de-sac on Palma Vista Avenue in Garden Grove, often sullied by gang graffiti, was being transformed into a mural, bursting with color and festooned with handprints from neighborhood kids. The festivities on Palma Vista Avenue on Sunday, May 21 was an example of community pride in action and the most recent in a series of activities organized by the city’s…