Port ea7499f5

Original Commit Message:

    Currently, we context allocate all parameters for generators.

    With this CL, we keep arguments on stack (unless they escape to inner
    closure) and copy them between the stack and the generator's register
    file on suspend/resume. This will save context allocation in most cases.

    - Suspend copies arguments and registers to the generator.
    - Resume copies only the registers from the generator, the arguments
      are copied by the ResumeGenerator trampoline.

R=jarin@chromium.org, joransiu@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=
LOG=N

Change-Id: I4a22024ce4e29a4e0217697a3b53b1c7bba0ddf1
Reviewed-on: https://chromium-review.googlesource.com/1072309Reviewed-by: Joran Siu <joransiu@ca.ibm.com>
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#53348}