Delete perf tests that are WontFixed.

LayoutTests/StaleTestExpectations

 # This file is for TestExpectations entries whose bugs haven't had any activity in 3 months.
 # Only imported test suites, virtual tests or platform/configuration-specific lines should
 # be moved here. The tests for stale cross-platform lines should just be deleted.
 #
 # Feel free to take ownership of any of these lines and get the test passing.
 
 webkit.org/b/109400 [ Win ] http/tests/css/css-image-loading.html [ WontFix ]
 
 # Overflowing LayoutUnits cause RenderGeometryMap assertions
 webkit.org/b/67434 [ Debug ] fast/overflow/overflow-height-float-not-removed-crash.html [ WontFix ]
@@ skipping 128 matching lines @@
 # We could fix this test for us and upstream it if the test shell user agent
 # would let us differentiate test_shell and WebKit DumpTreeNode.
 crbug.com/7482 [ Win Lion MountainLion Retina ] http/tests/misc/timer-vs-loading.html [ WontFix ]
 
 # This test isn't just slow -- sometimes it times out indefinitely.
 crbug.com/27569 [ Win ] http/tests/xmlhttprequest/redirect-cross-origin-tripmine.html [ Pass Timeout ] # Also Slow
 
 # Test introduced in r64817
 crbug.com/51571 [ Win ] http/tests/misc/bad-charset-alias.html [ WontFix ]
 
-# Mark as flaky initially while tuning on trybots
-# Most perf tests are also Slow
-Bug(nbarth) [ Release ] perf/array-push-pop.html [ WontFix ]
-Bug(nbarth) [ Release ] perf/array-reverse.html [ WontFix ]
-Bug(nbarth) [ Release ] perf/class-list-remove.html [ WontFix ]
-Bug(nbarth) [ Release ] perf/clone-with-focus.html [ WontFix ]
-Bug(nbarth) [ Release ] perf/document-contains.html [ WontFix ]
-Bug(nbarth) [ Release ] perf/htmlcollection-backwards-iteration.html [ WontFix ]
-Bug(nbarth) [ Release ] perf/htmlcollection-last-item.html [ WontFix ]
-Bug(nbarth) [ Release ] perf/mouse-event.html [ WontFix ]
-Bug(nbarth) [ Release ] perf/object-keys.html [ WontFix ]
-Bug(nbarth) [ Release ] perf/show-hide-table-rows.html [ Failure ] # Should be [ Failure Timeout ]?
-Bug(nbarth) [ Release ] perf/svg-path-appenditem.html [ WontFix ]
-Bug(nbarth) [ Release ] perf/table-rows-length-caching.html [ WontFix ]
-Bug(nbarth) [ Release ] perf/typing-at-end-of-line.html [ WontFix ]
-
 crbug.com/58257 [ Win ] http/tests/misc/last-modified-parsing.html [ WontFix ]
 
 # Failing from r69420
 crbug.com/58735 [ Win ] http/tests/misc/prefetch-purpose.html [ WontFix ]
 
 crbug.com/66087 [ Win ] http/tests/misc/no-last-modified.html [ WontFix ]
 
 # Random timeouts and failures going back a week.
 crbug.com/83290 [ Win ] http/tests/misc/link-rel-prefetch-and-subresource.html [ WontFix ]
 
@@ skipping 58 matching lines @@
 Bug(senorblanco) [ Win ] http/tests/w3c/webperf/submission/Google/HighResolutionTime/worker-dedicated-basic.html [ WontFix ]
 
 # These tests are too slow with our MESA backend.  We can re-enable when we have
 # bots running tests on real hardware. Don't want to just delete these because they
 # pass in the virtual test suite version.
 webkit.org/b/49629 compositing/lots-of-img-layers.html [ WontFix ]
 webkit.org/b/49629 compositing/lots-of-img-layers-with-opacity.html [ WontFix ]
 
 # Don't want to just delete this test since the virtual/softwarecompositing version passes.
 crbug.com/245630 compositing/overflow/overflow-positioning.html [ WontFix ]