Revert "made the root task a _dependency_ of the frame - this allows the user to call ac.assets.** and access the <head> tag before it's too late"
Revert "made the root task a _dependency_ of the frame - this allows the user to call ac.assets.** and access the <head> tag before it's too late"

This reverts commit 618363013c568c973e482e866d95143f2b0235a9.

yahoo/mojito-pipeline,aljimenez/mojito-pipeline