Bug 857356 - Make reftests/crashtest run without XBL scopes. r=bz

I talked about this with bz. The issue is that we have a lot of XUL reftests
that end up getting run as remote XUL given that the reftest harness loads
them with file:// URIs. But realistically most of them probably want to test
the fully-featured XBL environment that we provide to frontend and extensions.

So the compromise here is to do XBL scopes for content, and no XBL scopes
for reftests/crashtests.

layout/reftests/bugs/reftest.list

@@ -1169,9 +1169,9 @@ fuzzy(127,2) == 448193.html 448193-ref.html
 # == 448987.html 448987-ref.html  # Disabled for now - it needs privileges
 != 449149-1a.html about:blank
 != 449149-1b.html about:blank
-# Retry the above with our default remote XUL behavior
+# Retry the above with in-content XBL behavior
-test-pref(dom.use_xbl_scopes_for_remote_xul,false) != 449149-1a.html about:blank
+test-pref(dom.use_xbl_scopes_for_remote_xul,true) != 449149-1a.html about:blank
-test-pref(dom.use_xbl_scopes_for_remote_xul,false) != 449149-1b.html about:blank
+test-pref(dom.use_xbl_scopes_for_remote_xul,true) != 449149-1b.html about:blank
 == 449149-2.html 449149-2-ref.html
 == 449171-1.html 449171-ref.html
 == 449362-1.html 449362-1-ref.html

layout/reftests/invalidation/reftest.list

@@ -2,14 +2,6 @@
 == table-repaint-b.html table-repaint-b-ref.html
 == table-repaint-c.html table-repaint-c-ref.html
 == table-repaint-d.html table-repaint-d-ref.html
-# The below test involves XUL that expects to be able to use
+== 540247-1.xul 540247-1-ref.xul
-# Components.interfaces. This is kind of a tricky situation because reftests
-# actually run XUL with file:// URIs, and flip a pref that allows remote XUL
-# from the filesystem. And in fact, we have special behavior to allow access to
-# the Components object on remote XUL origins. However, we actually have an
-# override pref during automation that disables this behavior during automation.
-# Since reftests don't have SpecialPowers, our simplest path to victory here is
-# to override the override. Ugh.
-pref(dom.use_xbl_scopes_for_remote_xul,false) == 540247-1.xul 540247-1-ref.xul
 == 543681-1.html 543681-1-ref.html
 == test-image-layers.html test-image-layers-ref.html

layout/tools/reftest/b2g_start_script.js

@@ -9,7 +9,7 @@ function setDefaultPrefs() {
     var prefs = Components.classes["@mozilla.org/preferences-service;1"].
                 getService(Components.interfaces.nsIPrefService);
     var branch = prefs.getDefaultBranch("");
-    branch.setBoolPref("dom.use_xbl_scopes_for_remote_xul", true);
+    branch.setBoolPref("dom.use_xbl_scopes_for_remote_xul", false);
     branch.setBoolPref("gfx.color_management.force_srgb", true);
     branch.setBoolPref("browser.dom.window.dump.enabled", true);
     branch.setIntPref("ui.caretBlinkTime", -1);

layout/tools/reftest/reftest-cmdline.js

@@ -76,7 +76,11 @@ RefTestCmdLineHandler.prototype =
     var prefs = Components.classes["@mozilla.org/preferences-service;1"].
                 getService(Components.interfaces.nsIPrefService);
     var branch = prefs.getDefaultBranch("");
-    branch.setBoolPref("dom.use_xbl_scopes_for_remote_xul", true);
+    // For mochitests, we're more interested in testing the behavior of in-
+    // content XBL bindings, so we set this pref to true. In reftests, we're
+    // more interested in testing the behavior of XBL as it works in chrome,
+    // so we want this pref to be false.
+    branch.setBoolPref("dom.use_xbl_scopes_for_remote_xul", false);
     branch.setBoolPref("gfx.color_management.force_srgb", true);
     branch.setBoolPref("browser.dom.window.dump.enabled", true);
     branch.setIntPref("ui.caretBlinkTime", -1);