Downstream test: add AssetGraph
Downstream test: add AssetGraph

Fixes #1554
Closes gh-1557

ChromeDevTools/esprima,ariya/esprima,ChromeDevTools/esprima,jquery/esprima,ariya/esprima,ariya/esprima,bcbcarl/esprima,bcbcarl/esprima,ChromeDevTools/esprima,jquery/esprima,bcbcarl/esprima,jquery/esprima