Is there a way to add Google Chrome as an external web browser in Flash Builder Standalone for Mac?

You can do this from the UI in FB 4.5 - However, you need this exact path (unquoted and unescaped) in Preferences->Web Browser. Select "Use External Browser" and add the line below as the location (You may not need the 'name\="Google Chrome" bit, but looks like it worked all in one line for me):

/Applications/Google Chrome.app/Contents/MacOS/Google Chrome" name\="Google Chrome

You could create an executable here: /usr/local/bin/chrome with these contents:

#!/bin/shopen -a 'Google Chrome' $1 &

And then ensure Chrome's Preferences settings for "Web Browser" are this for external web browser "Google Chrome":

Name: Google ChromeLocation: /usr/local/bin/chromeParameters: %URL%

Update

As of Eclipse 4.3.1, the script approach (below) no longer works, but the simpler option of simply selecting "Google Chrome.app" as an external browser (using Eclipse UI) is fixed.

Old (obsolete) answer

My workaround was to create a shell script that opens Chrome (see below), and point Eclipse to this script. In this way Chrome is opened with 2 tabs - the home page and the requested page - but this was good enough for me.

#! /bin/shopen /Applications/Google\ Chrome.app $*