Get the milestone when a merged Chromium Gerrit tab is active (#722)

examples/milestones/manifest.json

@@ -0,0 +1,9 @@
+{
+  "name": "Milestones",
+  "version": "1.0",
+  "manifest_version": 3,
+  "action": {"default_popup": "popup.html"},
+  "description": "Chromium Release Milestones",
+  "host_permissions": [ "https://crrie.com/" ],
+  "permissions": [ "activeTab" ]
+}

examples/milestones/popup.html

@@ -0,0 +1 @@
+<script src="popup.js"></script>

examples/milestones/popup.js

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+chrome.tabs.query({active: true}).then(tabs => getMilestone(tabs));
+
+function getMilestone(tabs) {
+  const div = document.createElement("div");
+  document.body.appendChild(div);
+  const url = tabs[0].url;
+  const origin = 'https://chromium-review.googlesource.com';
+  const search = `^${origin}/c/chromium/src/\\+/(\\d+)`;
+  const match = url.match(search);
+  if (match != undefined && match.length == 2) {
+    getMilestoneForRevid(match[1]).then((milestone) =>
+      milestone != '' ? (div.innerText = `m${milestone}`) : window.close());
+  } else {
+    window.close();
+  }
+}
+
+function getMilestoneForRevid(revid) {
+  return fetch(`https://crrie.com/c/?r=${revid}`)
+  .then((res) => res.text());
+}