vtsyrklevich@ mentioned that he wanted a clang roll for some cfi-icall fixes.

Need r322139 for  issue 795807 .

I want r322905 for  issue 800169 

We also want Bob's r323164 LLD change to preserve the import library file timestamp when re-linking a DLL. I don't think we filed a crbug for that, it's just part of the general incremental linking bug in LLVM: https://bugs.llvm.org/show_bug.cgi?id=35917

r323362 should help a little with issue 801780.

We'd also like r323825 for bug 751218.

Need r323844 for  issue 807405 .

We need r323892 for  issue 784620 .

Correction to c#12, we need r323923.

I've started looking at the ToT bots. So far:

tot ubsan is red, not a blocker,  crbug.com/807631 
totlinuxthinlto, pcc is on it,  crbug.com/807402 
android x64 failing, infra problems? not blocking,  crbug.com/807966 
android asan failing, probably not blocking,  crbug.com/807967 
android cfi, not usually green so not blocking,  crbug.com/807969 
totmac failing to build libcxx, blocking,  crbug.com/807994 

Will now work my way over to the Windows side..

All the blockers are accounted for, and don't seem to actually be blocking the roll. Trying one here: https://chromium-review.googlesource.com/c/chromium/src/+/903927

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/ca5066b992b8a05e6a3df042f2c0e1766e13a565

commit ca5066b992b8a05e6a3df042f2c0e1766e13a565
Author: Hans Wennborg <hans@chromium.org>
Date: Fri Feb 09 12:48:33 2018

Roll clang 321529:324578

This changes the Clang version number from 6.0.0 to 7.0.0.

Bug:  803661 

Change-Id: Ib717cadcb3873d6dc3e49267629f7ffc1acf1df7
Reviewed-on: https://chromium-review.googlesource.com/903927
Reviewed-by: Nico Weber <thakis@chromium.org>
Commit-Queue: Hans Wennborg <hans@chromium.org>
Cr-Commit-Position: refs/heads/master@{#535693}
[modify] https://crrev.com/ca5066b992b8a05e6a3df042f2c0e1766e13a565/build/toolchain/toolchain.gni
[modify] https://crrev.com/ca5066b992b8a05e6a3df042f2c0e1766e13a565/tools/clang/scripts/update.py

The roll has stuck.

Perf report: https://chromeperf.appspot.com/group_report?rev=535693