Clang: suppress -Wdelayed-template-parsing-in-cxx20

This warning was added recently, see bug. Suppress it for now.

Bug: 1495100
Change-Id: I32909fb17aebfef8c649b86e40969486ee764b19
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4966627
Auto-Submit: Hans Wennborg <hans@chromium.org>
Commit-Queue: Hans Wennborg <hans@chromium.org>
Commit-Queue: Arthur Eubanks <aeubanks@google.com>
Reviewed-by: Arthur Eubanks <aeubanks@google.com>
Cr-Commit-Position: refs/heads/main@{#1213674}

build/config/compiler/BUILD.gn

diff --git a/build/config/compiler/BUILD.gn b/build/config/compiler/BUILD.gn
index b5b0b64..952b502 100644
--- a/build/config/compiler/BUILD.gn
+++ b/build/config/compiler/BUILD.gn
@@ -1884,6 +1884,11 @@
           cflags += [ "-Wno-thread-safety-reference" ]
         }
 
+        if (llvm_force_head_revision && is_win) {
+          # TODO(crbug.com/1495100): Evaluate and possibly enable.
+          cflags += [ "-Wno-delayed-template-parsing-in-cxx20" ]
+        }
+
         if (enable_precompiled_headers && !is_win) {
           cflags += [
             # TODO(crbug.com/1486799) Find a long-term solution.