Backed out changeset 309c896d7f8e (bug 1599943) for linux tsan mochitest failures on test_scrollbar_colors.html.

widget/tests/mochitest.ini

@@ -13,3 +13,4 @@ skip-if = toolkit != "windows" || e10s # Bug 1267491
 support-files = window_picker_no_crash_child.html
 [test_scrollbar_colors.html]
 skip-if = (os == 'linux' && headless) # bug 1460109
+fail-if = (os == 'linux' && os_version == '18.04') # Bug 1599943

widget/tests/test_scrollbar_colors.html

@@ -55,14 +55,13 @@ const MAC_REFERENCES = [
   ["0,255,255", 1760],
 ];
 
-// Values have been updated from 8100, 720, 1180 for linux1804
 const LINUX_REFERENCES = [
   // Yellow background
-  ["255,255,0", 7744],
+  ["255,255,0", 8100],
   // Blue scrollbar face
-  ["0,0,255", 1104],
+  ["0,0,255", 720],
   // Cyan scrollbar track
-  ["0,255,255", 1152],
+  ["0,255,255", 1180],
 ];
 
 let outer = document.querySelector(".outer");