[webtests] Temporarily disabling failing test for bug 1043030.

Bug: 1043030
Change-Id: Ifc97e8f42c67e21ca6418313469a933d08c3945f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2066779Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Kim-Anh Tran <kimanh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#743893}

third_party/blink/web_tests/TestExpectations

@@ -7,6 +7,9 @@
 # Further documentation:
 # https://chromium.googlesource.com/chromium/src/+/master/docs/testing/web_test_expectations.md
 
+# Temporarily disabled for 1043030
+crbug.com/1043030 http/tests/devtools/sources/source-frame-toolbar-items.js [ Pass Failure ]
+
 # Intentional failures to test the layout test system.
 harness-tests/crash.html [ Crash ]
 harness-tests/timeout.html [ Timeout ]