Gardening: Followup on NetworkService and virtual tests

FlagExpectations for NetworkService had failing expectations for
"cors-rfc1918" (including both non-virtual and virtual suites), but
this is already Skipped in the root TestExpectations
directory. Therefore the expectations had no effect, so remove
them.

Also, skip virtual/outofblink-cors entirely, since
these are intended to be run with NetworkService off.

Note that virtual tests were never actually run
with NetworkService on on the NetworkService bot until
last week (see https://crbug.com/908654).

Bug: 729849
Change-Id: I34f502f23fe026869daacbaf6cacf771195a6910
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/1356736
Commit-Queue: Matt Falkenhagen <falken@chromium.org>
Reviewed-by: Takashi Toyoshima <toyoshim@chromium.org>
Cr-Commit-Position: refs/heads/master@{#613007}

third_party/blink/web_tests/FlagExpectations/enable-features=NetworkService

 # These tests currently fail when run with --enable-features=NetworkService
 # See https://crbug.com/729849
 
-Bug(none) http/tests/security/cors-rfc1918 [ Crash Timeout ]
 Bug(none) http/tests/security/powerfulFeatureRestrictions/old-powerful-features-on-insecure-origin.html [ Pass Timeout ]
-Bug(none) virtual/outofblink-cors/http/tests/security/cors-rfc1918 [ Crash Timeout ]
-Bug(none) virtual/outofblink-cors/http/tests/security/powerfulFeatureRestrictions/old-powerful-features-on-insecure-origin.html [ Pass Timeout ]
-Bug(none) virtual/outofblink-cors-ns/http/tests/security/cors-rfc1918 [ Crash Timeout ]
-Bug(none) virtual/outofblink-cors-ns/http/tests/security/powerfulFeatureRestrictions/old-powerful-features-on-insecure-origin.html [ Pass Timeout ]
 
 # Only passes with Network Servce enabled (unfortunately these expectations still
 # allow Failure or Timeout from the top-level expectations though).
@@ -33,5 +28,9 @@ crbug.com/910212 virtual/reporting-api/external/wpt/content-security-policy/repo
 crbug.com/910212 virtual/reporting-api/external/wpt/content-security-policy/reporting-api/reporting-api-sends-reports-on-violation.https.sub.html [ Failure ]
 crbug.com/910212 virtual/reporting-api/external/wpt/content-security-policy/reporting-api/reporting-api-works-on-frame-src.https.sub.html [ Failure ]
 
-# Uncategorized failure.
-Bug(none) virtual/outofblink-cors/http/tests/security/isolatedWorld/cross-origin-xhr.html [ Failure ]
+# Skip virtual/outofblink-cors when NetworkService is on, since it's only
+# intended to be run with NetworkService off.
+Bug(none) virtual/outofblink-cors [ Skip ]
+# Skip virtual/outofblink-cors-ns on this bot, since when run normally it
+# already forces NetworkService on, so there is no need to run it again here.
+Bug(none) virtual/outofblink-cors-ns [ Skip ]