Turn off WKHTTPSystemCookieStore for M71

This cl is to be merged to M71

Change-Id: Ic2d3ab3afd52217f1dc06ca15bc67cfdb920f42d
Reviewed-on: https://chromium-review.googlesource.com/c/1299734
Commit-Queue: Mohammad Refaat <mrefaat@chromium.org>
Reviewed-by: Eugene But <eugenebut@chromium.org>
Cr-Commit-Position: refs/heads/master@{#602884}

ios/web/features.mm

@@ -17,7 +17,7 @@ const base::Feature kSlimNavigationManager{"SlimNavigationManager",
                                            base::FEATURE_DISABLED_BY_DEFAULT};
 
 const base::Feature kWKHTTPSystemCookieStore{"WKHTTPSystemCookieStore",
-                                             base::FEATURE_ENABLED_BY_DEFAULT};
+                                             base::FEATURE_DISABLED_BY_DEFAULT};
 
 const base::Feature kCrashOnUnexpectedURLChange{
     "CrashOnUnexpectedURLChange", base::FEATURE_ENABLED_BY_DEFAULT};