Update site-per-process expectations for off-main-thread-fetch virtual test suite.

https://codereview.chromium.org/2882383002 introduced this virtual
test suite, breaking expectations for a couple of tests that need to be
excluded for --site-per-process.

BUG=477150
NOTRY=true

Review-Url: https://codereview.chromium.org/2888733003
Cr-Commit-Position: refs/heads/master@{#472240}

third_party/WebKit/LayoutTests/FlagExpectations/site-per-process

@@ -96,6 +96,7 @@ crbug.com/606594 virtual/mojo-loading/http/tests/local/serviceworker/fetch-reque
 # https://crbug.com/607991 - MockWebClipboardImpl not replicated across OOPIFs.
 crbug.com/607991 http/tests/misc/copy-resolves-urls.html [ Failure ]
 crbug.com/607991 virtual/mojo-loading/http/tests/misc/copy-resolves-urls.html [ Failure ]
+crbug.com/607991 virtual/off-main-thread-fetch/http/tests/misc/copy-resolves-urls.html [ Failure ]
 
 # https://crbug.com/608780 - window.performance doesn't work with OOPIFs
 crbug.com/608780 http/tests/w3c/webperf/submission/Intel/resource-timing/test_resource_timing_cross_origin_redirect.html [ Failure ]
@@ -174,6 +175,7 @@ crbug.com/678491 virtual/mojo-loading/http/tests/misc/webtiming-no-origin.html [
 # These tests sometimes fail on usual bots but crash w/ --site-per-process.
 crbug.com/678492 http/tests/misc/webtiming-ssl.php [ Crash ]
 crbug.com/678492 virtual/mojo-loading/http/tests/misc/webtiming-ssl.php [ Crash ]
+crbug.com/678492 virtual/off-main-thread-fetch/http/tests/misc/webtiming-ssl.php [ Crash ]
 
 # Slow tests. These are listed in SlowTests listed here also because
 # expectations are unfortunately not inherited automatically (e.g. see