[New sample] Open Chrome API reference page (omnibox, alarms, messaging sample) (#848)

* First draft

* Rename folder

* Tweak comments

* Update index.html

* remove extra closing div

* Rename sw file

* Apply first round of @sebastianbenz suggestions

* Fix import

* Update popover

* Second tech review round

functional-samples/tutorial.open-api-reference/api-list.js

@@ -0,0 +1,81 @@
+export default [
+  {
+    content: 'commands',
+    description:
+      'Use the <match>Commands API</match> to add a keyboard shortcuts.'
+  },
+  {
+    content: 'contextmenus',
+    description:
+      "Use the <match>ContextMenus API</match> to add a custom item to Chrome's context menu."
+  },
+  {
+    content: 'declarativeNetRequest',
+    description:
+      'Use the <match>DeclarativeNetRequest API</match> to block or modify network requests.'
+  },
+  {
+    content: 'downloads',
+    description:
+      'Use the <match>Downloads API</match> to programmatically manipulate downloads.'
+  },
+  {
+    content: 'i18n',
+    description: 'Use the <match>i18n API</match> to localize your extension'
+  },
+  {
+    content: 'identity',
+    description:
+      'Use the <match>Identity API</match> to get OAuth2 access tokens.'
+  },
+  {
+    content: 'notifications',
+    description:
+      'Use the <match>Notifications API</match> show notifications to users in the system tray.'
+  },
+  {
+    content: 'offscreen',
+    description:
+      'Use the <match>Offscreen API</match> to create and manage offscreen documents.'
+  },
+  {
+    content: 'omnibox',
+    description:
+      "Use the <match>Omnibox API</match> to register a keyword with Chrome's address bar."
+  },
+  {
+    content: 'permissions',
+    description:
+      'Use the <match>Permissions API</match> to request optional permissions at run time.'
+  },
+  {
+    content: 'runtime',
+    description:
+      'Use the <match>Runtime API</match> pass messages, manage extension lifecycle, and access other helper utils.'
+  },
+  {
+    content: 'scripting',
+    description:
+      'Use the <match>Scripting API</match> to execute scripts in different contexts.'
+  },
+  {
+    content: 'storage',
+    description:
+      'Use the <match>Storage API</match> to store, retrieve, and track changes to user data.'
+  },
+  {
+    content: 'tabs',
+    description:
+      'Use the <match>Tabs API</match> to create, update and manipulate tabs.'
+  },
+  {
+    content: 'topSites',
+    description:
+      'Use the <match>TopSites API</match> to access the most visited sites that are displayed on the new tab page.'
+  },
+  {
+    content: 'webNavigation',
+    description:
+      'Use the <match>WebNavigation API</match> to receive notifications about the status of navigation requests in-flight.'
+  }
+];