Port c462ddc8

Original Commit Message:

    This makes sure that {JSFunction} invocations always load the code start
    address into the fixed {kJavaScriptCallCodeStartRegister} register. This
    allows us to perform PC-relative operations more effective. For now this
    only applies to code with {kCallJSFunction} linkage.

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

Change-Id: If346a3cbaea820b1fcec38c5105605496961a888
Reviewed-on: https://chromium-review.googlesource.com/938721Reviewed-by: Joran Siu <joransiu@ca.ibm.com>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#51608}