Bug 1518799: Show a custom page on startup on Nightly on a specific date. r=Gijs

We want to show an informative message about dedicated profiles per channel to
users of Nightly on a specific date. We currently only have the ability to do
this when the version changes. This adds the ability to show a page once on
startup on a specific date.

This will probably be backed out past that date.

Differential Revision: https://phabricator.services.mozilla.com/D16249

--HG--
extra : rebase_source : 2da25281b9a9e52f11af43161f48e9db5a7da984
extra : source : eace4709948cdf060a36a60c00eeb286cb7acb17

browser/branding/nightly/pref/firefox-branding.js

@@ -2,6 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+pref("startup.homepage_override_nightly.20190116", "https://www.mozilla.org/firefox/dedicated-profiles/");
 pref("startup.homepage_override_url", "https://www.mozilla.org/projects/firefox/%VERSION%/whatsnew/?oldversion=%OLD_VERSION%");
 pref("startup.homepage_welcome_url", "https://www.mozilla.org/projects/firefox/%VERSION%/firstrun/");
 pref("startup.homepage_welcome_url.additional", "");

browser/components/nsBrowserContentHandler.js

@@ -61,10 +61,18 @@ function resolveURIInternal(aCmdLine, aArgument) {
 
 var gFirstWindow = false;
 
+function getNormalizedDate() {
+  let pad = num => ("" + num).padStart(2, "0");
+
+  let date = new Date();
+  return `${date.getFullYear()}${pad(date.getMonth() + 1)}${pad(date.getDate())}`;
+}
+
 const OVERRIDE_NONE        = 0;
 const OVERRIDE_NEW_PROFILE = 1;
 const OVERRIDE_NEW_MSTONE  = 2;
 const OVERRIDE_NEW_BUILD_ID = 3;
+const OVERRIDE_NIGHTLY     = 4;
 /**
  * Determines whether a home page override is needed.
  * Returns:
@@ -76,6 +84,15 @@ const OVERRIDE_NEW_BUILD_ID = 3;
  *  OVERRIDE_NONE otherwise.
  */
 function needHomepageOverride(prefb) {
+  let isInTests = Cu.isInAutomation || Services.prefs.getBoolPref("marionette.enabled", false);
+  if (AppConstants.NIGHTLY_BUILD && !isInTests) {
+    let pref = `startup.homepage_override_nightly.${getNormalizedDate()}`;
+    let url = Services.prefs.getCharPref(pref, "");
+    if (url) {
+      return OVERRIDE_NIGHTLY;
+    }
+  }
+
   var savedmstone = prefb.getCharPref("browser.startup.homepage_override.mstone", "");
 
   if (savedmstone == "ignore")
@@ -544,6 +561,12 @@ nsBrowserContentHandler.prototype = {
               UpdatePing.handleUpdateSuccess(old_mstone, old_buildId);
             }
             break;
+          case OVERRIDE_NIGHTLY:
+            // Opens a page on the first startup on a particular day.
+            let pref = `startup.homepage_override_nightly.${getNormalizedDate()}`;
+            overridePage = Services.prefs.getCharPref(pref);
+            Services.prefs.setCharPref(pref, "");
+            break;
         }
       }
     } catch (ex) {}