This reverts commit 63ecddc8.

Reason for revert:
https://build.chromium.org/p/client.v8/builders/V8%20Linux64%20-%20internal%20snapshot/builds/14773

Original change's description:
> [runtime] Remove the construct_stub field of the SFI
> 
> Don't dispatch based on the construct_stub field anymore. Rather than
> read it out and jump to the construct stub, we can switch on the
> builtin_id.
> 
> Builtins will always have builtin_id as a Smi, so this signals we need
> to jump to JSBuiltinsConstructStub. The only exception is for uncompiled
> functions, which will have kCompileLazy as the builtin_id, but need to
> jump to the generic stub instead.
> 
> API function calls will have a FunctionTemplateInfo in the SFI
> function_data field, and need to go to the builtins stub as well.
> 
> The final case is everything else, which should go to the generic stub.
> 
> Bug: v8:7503
> Change-Id: I14790a5f9784dc0d940bf10a05f5310026e1d482
> Reviewed-on: https://chromium-review.googlesource.com/980941
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
> Commit-Queue: Peter Marshall <petermarshall@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#52345}

TBR=petermarshall@chromium.org,leszeks@chromium.org,bmeurer@chromium.org

Change-Id: I2031913ab5a12018ad932f920792aa1f6faa5e22
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:7503
Reviewed-on: https://chromium-review.googlesource.com/995293Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52346}