Fix bug in bubble chart example with unstable color coding

inst/examples/bubble/server.R

@@ -4,11 +4,14 @@ shinyServer(function(input, output, session) {
  yearData <- reactive({
  # Filter to the desired year, and put the columns
  # in the order that Google's Bubble Chart expects
- # them (name, x, y, color, size)
+ # them (name, x, y, color, size). Also sort by region
+ # so that Google Charts colors the regions consistently
+ # (thanks Prof. Gelman).
  df <- data %.%
  filter(Year == input$year) %.%
  select(Country, Health.Expenditure, Life.Expectancy,
- Region, Population)
+ Region, Population) %.%
+ arrange(Region)
  })
 
  output$chart <- reactive({