scripts

check to see if the supplied variant is valid

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#                                                                #
#              Read me before you modify this code               #
#                                                                #
#   This function sets ANDROID_BUILD_PATHS to what it is adding  #
#   to PATH, and the next time it is run, it removes that from   #
#   PATH.  This is required so lunch can be run more than once   #
#   and still have working paths.                                #
#                                                                #
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