Revert of [turbofan] Don't take into account source size for inlining heuristics. (patchset #4 id:60001 of https://codereview.chromium.org/2361813002/ )

Reason for revert:
timeouts on windows:
https://build.chromium.org/p/client.v8/builders/V8%20Win64%20-%20debug/builds/12504

Original issue's description:
> [turbofan] Don't take into account source size for inlining heuristics.
>
> The source size is not a real indicator for whether or not to inline a
> certain function.
>
> R=ishell@chromium.org, jarin@chromium.org
> BUG=v8:3354,v8:5267
>
> Committed: https://chromium.googlesource.com/v8/v8/+/1b33028607637ba8cb2d60433811f825b00a0cc1

TBR=ishell@chromium.org,jarin@chromium.org,bmeurer@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:3354,v8:5267

Review-Url: https://codereview.chromium.org/2362853003
Cr-Commit-Position: refs/heads/master@{#39661}