This enables Ignition unconditionally for all code that is destined for
optimization with TurboFan. This ensures all optimization attempts will
go through the BytecodeGraphBuilder and that the AstGraphBuilder pipe is
dried out in practice.

patch from issue 2427953002 at patchset 120001 (http://crrev.com/2427953002#ps120001)

R=mvstanton@chromium.org,rmcilroy@chromium.org

Review-Url: https://codereview.chromium.org/2453973004
Cr-Commit-Position: refs/heads/master@{#40663}