Bug 1234520 - Re-enable test_bug344861.html, test_bug369370.html, test_bug741266.html on Windows. r=dao

Differential Revision: https://phabricator.services.mozilla.com/D112471

docshell/test/navigation/mochitest.ini

@@ -89,7 +89,7 @@ support-files = file_beforeunload_and_bfcache.html
 [test_bug278916.html]
 [test_bug279495.html]
 [test_bug344861.html]
-skip-if = toolkit == "android" || toolkit == "windows" # disabled on Windows because of bug 1234520
+skip-if = toolkit == "android"
 [test_bug386782.html]
 [test_bug430624.html]
 [test_bug430723.html]

dom/html/test/mochitest.ini

@@ -533,7 +533,7 @@ tags = openwindow
 [test_bug340017.xhtml]
 [test_bug359657.html]
 [test_bug369370.html]
-skip-if = toolkit == "android" || toolkit == "windows" || os == 'linux' # disabled on Windows because of bug 1234520, disabled on linux bug 1258103
+skip-if = toolkit == "android" || os == 'linux' # disabled on linux bug 1258103
 [test_bug380383.html]
 [test_bug402680.html]
 [test_bug403868.html]
@@ -560,7 +560,7 @@ skip-if = true # Disabled permanently (bug 559932).
 [test_bug677495.html]
 [test_bug677495-1.html]
 [test_bug741266.html]
-skip-if = toolkit == "android" || toolkit == "windows" # Android: needs control of popup window size, windows(bug 1234520)
+skip-if = toolkit == "android" # Android: needs control of popup window size
 [test_non-ascii-cookie.html]
 support-files = file_cookiemanager.js
 [test_bug765780.html]