From ab79cc0e39783c41e39307b46e71306cdfc90907 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Emilio=20Cobos=20=C3=81lvarez?= <emilio@crisal.io>
Date: Mon, 25 May 2020 23:54:10 +0000
Subject: [PATCH] style: Implement the ::file-chooser-button pseudo-element.

As per https://github.com/w3c/csswg-drafts/issues/5049.

Don't enable it unconditionally just yet, as the name may change.

I had to move some rules in forms.css because otherwise you get
specificity conflicts.

Differential Revision: https://phabricator.services.mozilla.com/D76214
---
 components/style/gecko/pseudo_element.rs | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/components/style/gecko/pseudo_element.rs b/components/style/gecko/pseudo_element.rs
index b537295f785..631172d9511 100644
--- a/components/style/gecko/pseudo_element.rs
+++ b/components/style/gecko/pseudo_element.rs
@@ -37,7 +37,8 @@ impl ::selectors::parser::PseudoElement for PseudoElement {
             PseudoElement::Before |
                 PseudoElement::After |
                 PseudoElement::Marker |
-                PseudoElement::Placeholder
+                PseudoElement::Placeholder |
+                PseudoElement::FileChooserButton
         )
     }
 
@@ -159,12 +160,12 @@ impl PseudoElement {
 
     /// Whether this pseudo-element is enabled for all content.
     pub fn enabled_in_content(&self) -> bool {
-        if (self.flags() & structs::CSS_PSEUDO_ELEMENT_ENABLED_IN_UA_SHEETS_AND_CHROME) != 0 {
-            return false;
-        }
         match *self {
             PseudoElement::MozFocusOuter => static_prefs::pref!("layout.css.moz-focus-outer.enabled"),
-            _ => true,
+            PseudoElement::FileChooserButton => static_prefs::pref!("layout.css.file-chooser-button.enabled"),
+            _ => {
+                (self.flags() & structs::CSS_PSEUDO_ELEMENT_ENABLED_IN_UA_SHEETS_AND_CHROME) == 0
+            }
         }
     }