Mark two tests as failing on Webkit Linux Leak.

http/tests/devtools/tracing/timeline-paint/timeline-paint.js
http/tests/devtools/tracing/timeline-misc/timeline-event-causes.js

TBR=petermarshall@chromium.org

Bug: 1046784
Change-Id: If96dfea5f642fa1602be56d00008a5b3495769ac
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2314756Reviewed-by: James MacLean <wjmaclean@chromium.org>
Commit-Queue: James MacLean <wjmaclean@chromium.org>
Cr-Commit-Position: refs/heads/master@{#791257}

third_party/blink/web_tests/TestExpectations

@@ -6864,6 +6864,9 @@ crbug.com/1105172 http/tests/devtools/sources/debugger-breakpoints/use-possible-
 crbug.com/1107722 [ Mac ] http/tests/devtools/tracing/timeline-js/timeline-script-id.js [ Pass Failure ]
 crbug.com/1107722 [ Mac ] virtual/threaded/http/tests/devtools/tracing/timeline-misc/timeline-event-causes.js [ Pass Failure ]
 crbug.com/1107923 [ Mac10.15 ] inspector-protocol/debugger/wasm-streaming-url.js [ Pass Timeout Failure ]
+# Failing on Webkit Linux Leak
+crbug.com/1046784 [ Linux ] http/tests/devtools/tracing/timeline-paint/timeline-paint.js [ Pass Failure ]
+crbug.com/1046784 [ Linux ] http/tests/devtools/tracing/timeline-misc/timeline-event-causes.js [ Pass Failure ]
 
 # Sheriff 2020-07-23
 crbug.com/1108728 [ Mac ] external/wpt/html/cross-origin-opener-policy/reporting/access-reporting/opener-accessed_openee-coop-ro.https.html [ Failure ]