BUG=v8:5294

Change-Id: If45f25aae8de526027b7851cb4efe0ccf4a7c4b1
Reviewed-on: https://chromium-review.googlesource.com/444226
Commit-Queue: Marja Hölttä <marja@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43388}

Also introduces FFIType separate from MachineType for express ffi
signatures.

BUG=v8:4456

Review-Url: https://codereview.chromium.org/2639163004
Cr-Commit-Position: refs/heads/master@{#42612}

FFI Compiler outline based on code stub assembler. We are looking to land this frame to allow specific type translation implementations to proceed in parallel.

BUG=v8:4456

Review-Url: https://codereview.chromium.org/2607993003
Cr-Commit-Position: refs/heads/master@{#42475}