Unexpire Sanitizer API flag.

The Sanitizer API is presently being re-defined. Sooner or later,
our implementation will follow the new definition. We're un-expiring
ths flag for this, so that we can later extend it to toggle between
the current and the future versions.

Bug: 1419415, 1101982
Change-Id: I6ddaa2829bc5cb2d3511a1789ad5e9abfebf7b0e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4644178
Commit-Queue: Yifan Luo <lyf@chromium.org>
Reviewed-by: Yifan Luo <lyf@chromium.org>
Quick-Run: Yifan Luo <lyf@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1164673}

chrome/browser/flag-metadata.json

@@ -6833,7 +6833,7 @@
   {
     "name": "sanitizer-api",
     "owners": [ "//third_party/blink/renderer/modules/sanitizer_api/OWNERS" ],
-    "expiry_milestone": 109
+    "expiry_milestone": 130
   },
   {
     "name": "scalable-iph",