Remove universal access permission from web tests

The TestRunner for web tests used to grant the universal access
permission to all origins by default. That is, all origin boundary
checks are disabled. However, it's no longer needed, and it's hard to
support dynamic configuration of the security check around the origin
boundary.

This CL drops the permission as a preparation to remove the settings
item itself.

Change-Id: I22cd23d10fe1f0d10a4a64a3d5404adda129645c
Reviewed-on: https://chromium-review.googlesource.com/c/1454163Reviewed-by: Kent Tamura <tkent@chromium.org>
Commit-Queue: Taiju Tsuiki <tzik@chromium.org>
Cr-Commit-Position: refs/heads/master@{#629106}

content/shell/test_runner/test_preferences.cc

@@ -29,10 +29,7 @@ void TestPreferences::Reset() {
   loads_images_automatically = true;
   plugins_enabled = true;
   caret_browsing_enabled = false;
-
-  // Allow those web tests running as local files, i.e. under
-  // web_tests/http/tests/local, to access http server.
-  allow_universal_access_from_file_urls = true;
+  allow_universal_access_from_file_urls = false;
 
 #if defined(OS_MACOSX)
   editing_behavior = WebSettings::EditingBehavior::kMac;