Add DwoC to monitor for cases with zero BIids.

This CL adds a DwoC to monitor for cases where CanAccessDataForOrigin
encounters zero BrowsingInstanceIds. We believe these were fixed in
https://chromium-review.googlesource.com/c/chromium/src/+/2523732 and
https://chromium-review.googlesource.com/c/chromium/src/+/2522904 but
in case there are other pathways that can lead to this condition we
need to be vigilant.

This is being landed in a separate CL to make it easy to revert.

Bug: 1135539, 1141721
Change-Id: I387693c4d8543bda79cee5e2c2d2c9cae57b0f0a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2532873Reviewed-by: Alex Moshchuk <alexmos@chromium.org>
Commit-Queue: James MacLean <wjmaclean@chromium.org>
Cr-Commit-Position: refs/heads/master@{#826458}

content/browser/child_process_security_policy_impl.cc

@@ -1636,6 +1636,12 @@ bool ChildProcessSecurityPolicyImpl::CanAccessDataForOrigin(
         // BrowsingInstances are registered in the process. Allow this for now,
         // to maintain legacy behavior, until we rule out all the ways it can
         // happen.
+        LogCanAccessDataForOriginCrashKeys(
+            expected_process_lock.ToString(),
+            GetKilledProcessOriginLock(security_state), url.GetOrigin().spec(),
+            "process is locked, but there are no BrowsingInstanceIds "
+            "registered");
+        base::debug::DumpWithoutCrashing();
         return true;
       }
       for (auto browsing_instance_id :