Bug 40002: Remove about:pioneer

Firefox Pioneer is an opt-in program in which people volunteer to
participate in studies that collect detailed, sensitive data about
how they use their browser.

browser/components/about/AboutRedirector.cpp

@@ -114,8 +114,6 @@ static const RedirEntry kRedirMap[] = {
      nsIAboutModule::URI_MUST_LOAD_IN_CHILD |
          nsIAboutModule::URI_SAFE_FOR_UNTRUSTED_CONTENT |
          nsIAboutModule::ALLOW_SCRIPT | nsIAboutModule::HIDE_FROM_ABOUTABOUT},
-    {"pioneer", "chrome://browser/content/pioneer.html",
-     nsIAboutModule::ALLOW_SCRIPT | nsIAboutModule::HIDE_FROM_ABOUTABOUT},
 #ifdef TOR_BROWSER_UPDATE
     {"tbupdate", "chrome://browser/content/abouttbupdate/aboutTBUpdate.xhtml",
      nsIAboutModule::URI_SAFE_FOR_UNTRUSTED_CONTENT |

browser/components/about/components.conf

@@ -14,7 +14,6 @@ pages = [
     'logins',
     'newinstall',
     'newtab',
-    'pioneer',
     'pocket-saved',
     'pocket-signup',
     'policies',