feat: import code from CWS listing

This is an import from the code as uploaded to the Chrome Web Store in
version 0.1.4.

It also adds a .gitreview file to facilitate uploading the code for
review in Gerrit.

Change-Id: Ib15fdf3b9508b2cc9e49ac0414fcaea3e6441bbb
diff --git a/pageevent.js b/pageevent.js
new file mode 100644
index 0000000..ad7ac40
--- /dev/null
+++ b/pageevent.js
@@ -0,0 +1,14 @@
+chrome.runtime.onInstalled.addListener(function() {
+  chrome.declarativeContent.onPageChanged.removeRules(undefined, function() {
+     chrome.declarativeContent.onPageChanged.addRules([
+       {
+         conditions: [
+           new chrome.declarativeContent.PageStateMatcher({
+             pageUrl: { schemes: ['http', 'https'] },
+           })
+         ],
+        actions: [ new chrome.declarativeContent.ShowPageAction() ]
+      }
+    ]);
+  });
+});