From bb5de5833cdb79fa66cded04856673608e258a47 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Emilio=20Cobos=20=C3=81lvarez?= <emilio@crisal.io>
Date: Thu, 23 Jun 2022 22:38:02 +0000
Subject: [PATCH] style: Improve LookAndFeel color caching

To be honest, I'm a bit baffled that bug 1773795 caused a performance
regression, but I think it's because the standins codepath is not really
cached, so system colors that are "spoofed" always go through the
massive switch, which could potentially be expensive.

To fix, this, rejigger a bit the caches so that we key on both
color-scheme and use-standins. Also, while at it, make the set of colors
we spoof a single bitflag check, rather than relying on the compiler to
do something potentially smart with it.

I had to shuffle the order of colors around so that the expression to
initialize the bitfield is constexpr (doesn't go over 1 << 64), but
other than that this patch should be relatively straight-forward.

Differential Revision: https://phabricator.services.mozilla.com/D150100
---
 components/style/values/specified/color.rs | 105 +++++++++++----------
 1 file changed, 53 insertions(+), 52 deletions(-)

diff --git a/components/style/values/specified/color.rs b/components/style/values/specified/color.rs
index 674d51ad211..1260f1ebc65 100644
--- a/components/style/values/specified/color.rs
+++ b/components/style/values/specified/color.rs
@@ -129,54 +129,6 @@ pub enum Color {
 #[derive(Clone, Copy, Debug, MallocSizeOf, Parse, PartialEq, ToCss, ToShmem)]
 #[repr(u8)]
 pub enum SystemColor {
-    #[parse(condition = "ParserContext::in_ua_or_chrome_sheet")]
-    TextSelectDisabledBackground,
-    #[css(skip)]
-    TextSelectAttentionBackground,
-    #[css(skip)]
-    TextSelectAttentionForeground,
-    #[css(skip)]
-    TextHighlightBackground,
-    #[css(skip)]
-    TextHighlightForeground,
-    #[css(skip)]
-    IMERawInputBackground,
-    #[css(skip)]
-    IMERawInputForeground,
-    #[css(skip)]
-    IMERawInputUnderline,
-    #[css(skip)]
-    IMESelectedRawTextBackground,
-    #[css(skip)]
-    IMESelectedRawTextForeground,
-    #[css(skip)]
-    IMESelectedRawTextUnderline,
-    #[css(skip)]
-    IMEConvertedTextBackground,
-    #[css(skip)]
-    IMEConvertedTextForeground,
-    #[css(skip)]
-    IMEConvertedTextUnderline,
-    #[css(skip)]
-    IMESelectedConvertedTextBackground,
-    #[css(skip)]
-    IMESelectedConvertedTextForeground,
-    #[css(skip)]
-    IMESelectedConvertedTextUnderline,
-    #[css(skip)]
-    SpellCheckerUnderline,
-    #[css(skip)]
-    ThemedScrollbar,
-    #[css(skip)]
-    ThemedScrollbarInactive,
-    #[css(skip)]
-    ThemedScrollbarThumb,
-    #[css(skip)]
-    ThemedScrollbarThumbHover,
-    #[css(skip)]
-    ThemedScrollbarThumbActive,
-    #[css(skip)]
-    ThemedScrollbarThumbInactive,
     Activeborder,
     /// Background in the (active) titlebar.
     Activecaption,
@@ -196,6 +148,10 @@ pub enum SystemColor {
     #[parse(aliases = "-moz-fieldtext")]
     Fieldtext,
 
+    /// Combobox widgets
+    MozComboboxtext,
+    MozCombobox,
+
     Graytext,
     Highlight,
     Highlighttext,
@@ -331,16 +287,61 @@ pub enum SystemColor {
     #[parse(aliases = "-moz-visitedhyperlinktext")]
     Visitedtext,
 
-    /// Combobox widgets
-    MozComboboxtext,
-    MozCombobox,
-
     /// Color of tree column headers
     #[parse(condition = "ParserContext::in_ua_or_chrome_sheet")]
     MozColheadertext,
     #[parse(condition = "ParserContext::in_ua_or_chrome_sheet")]
     MozColheaderhovertext,
 
+    #[parse(condition = "ParserContext::in_ua_or_chrome_sheet")]
+    TextSelectDisabledBackground,
+    #[css(skip)]
+    TextSelectAttentionBackground,
+    #[css(skip)]
+    TextSelectAttentionForeground,
+    #[css(skip)]
+    TextHighlightBackground,
+    #[css(skip)]
+    TextHighlightForeground,
+    #[css(skip)]
+    IMERawInputBackground,
+    #[css(skip)]
+    IMERawInputForeground,
+    #[css(skip)]
+    IMERawInputUnderline,
+    #[css(skip)]
+    IMESelectedRawTextBackground,
+    #[css(skip)]
+    IMESelectedRawTextForeground,
+    #[css(skip)]
+    IMESelectedRawTextUnderline,
+    #[css(skip)]
+    IMEConvertedTextBackground,
+    #[css(skip)]
+    IMEConvertedTextForeground,
+    #[css(skip)]
+    IMEConvertedTextUnderline,
+    #[css(skip)]
+    IMESelectedConvertedTextBackground,
+    #[css(skip)]
+    IMESelectedConvertedTextForeground,
+    #[css(skip)]
+    IMESelectedConvertedTextUnderline,
+    #[css(skip)]
+    SpellCheckerUnderline,
+    #[css(skip)]
+    ThemedScrollbar,
+    #[css(skip)]
+    ThemedScrollbarInactive,
+    #[css(skip)]
+    ThemedScrollbarThumb,
+    #[css(skip)]
+    ThemedScrollbarThumbHover,
+    #[css(skip)]
+    ThemedScrollbarThumbActive,
+    #[css(skip)]
+    ThemedScrollbarThumbInactive,
+
     #[css(skip)]
     End, // Just for array-indexing purposes.
 }