This is part of the effort to decrease the amount of undefined behavior.
that v8 relies on.

The main change here is to represent types with class Type rather than
with pointer Type*. To make the CL smaller, I used an operator overload
hack to separate the change from `->` to `.`. I am working on a CL that
will remove the operator and change all those arrows to dots.

Bug: v8:3770
Change-Id: I71a197cb739a1467937bc95c2a757fab0469aa22
Reviewed-on: https://chromium-review.googlesource.com/1032551
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52872}

This is a reland of 6da438fd

Original change's description:
> [runtime] introduced instrance type for each context type
> 
> Each context type get own instance type:
> - we can make CSA checks more strict in couple places,
> - it is requires step for advanced evaluation without side effects.
> 
> R=yangguo@chromium.org
> 
> Bug: v8:7588
> Change-Id: I585e8b55a280a909fc3c6069ed30e34b7040d0c7
> Reviewed-on: https://chromium-review.googlesource.com/977041
> Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#52191}

Bug: v8:7588
Change-Id: I80110ff814c0315d7ca694b7d0aef5b10df614f0
Reviewed-on: https://chromium-review.googlesource.com/978584Reviewed-by: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52196}

This reverts commit 6da438fd.

Reason for revert:
https://build.chromium.org/p/client.v8/builders/V8%20Linux%20-%20nosnap%20-%20debug/builds/18287

Original change's description:
> [runtime] introduced instrance type for each context type
> 
> Each context type get own instance type:
> - we can make CSA checks more strict in couple places,
> - it is requires step for advanced evaluation without side effects.
> 
> R=​yangguo@chromium.org
> 
> Bug: v8:7588
> Change-Id: I585e8b55a280a909fc3c6069ed30e34b7040d0c7
> Reviewed-on: https://chromium-review.googlesource.com/977041
> Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#52191}

TBR=yangguo@chromium.org,mstarzinger@chromium.org,kozyatinskiy@chromium.org

Change-Id: I17a24b5b99552941d7a8ec54ebf6d11d6d1a66d8
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:7588
Reviewed-on: https://chromium-review.googlesource.com/977974Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52193}

Each context type get own instance type:
- we can make CSA checks more strict in couple places,
- it is requires step for advanced evaluation without side effects.

R=yangguo@chromium.org

Bug: v8:7588
Change-Id: I585e8b55a280a909fc3c6069ed30e34b7040d0c7
Reviewed-on: https://chromium-review.googlesource.com/977041
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52191}

This makes all inline allocation constructions go through the existing
{AllocationBuilder} helper class. It hence ensures there is a single
place for all sanity checking and and makes use-sites easier to read.

R=jarin@chromium.org

Change-Id: Ib5daf48acd93c631fccdfa095eda1afda7048115
Reviewed-on: https://chromium-review.googlesource.com/709056
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48502}