DevTools: flaky test - elements-panel-rewrite-href.js

This test became flaky after migrating it to the new test framework. Looks
like there's some sort of the race with the base tag. Will unflake this soon.

TBR=dgozman@chromium.org

Bug: 667560
Change-Id: Idbc7c298a0e9f45703586d66aff39a45c92b76cd
Reviewed-on: https://chromium-review.googlesource.com/773490
Commit-Queue: Will Chen <chenwilliam@chromium.org>
Reviewed-by: Will Chen <chenwilliam@chromium.org>
Cr-Commit-Position: refs/heads/master@{#517167}

third_party/WebKit/LayoutTests/TestExpectations

@@ -4122,12 +4122,13 @@ crbug.com/783229 external/wpt/cookie-store/one_simple_origin_cookie_static.tenta
 crbug.com/785179 [ Win7 Debug ] http/tests/devtools/console/console-viewport-stick-to-bottom.js [ Skip ]
 crbug.com/785179 [ Mac10.11 ] virtual/mojo-loading/http/tests/devtools/console/console-viewport-stick-to-bottom.js [ Failure Pass ]
 crbug.com/785179 [ Win7 Debug ] virtual/mojo-loading/http/tests/devtools/console/console-viewport-stick-to-bottom.js [ Skip ]
-crbug.com/785187 [ Mac ] virtual/mojo-loading/http/tests/devtools/elements/elements-panel-rewrite-href.js [ Skip ]
-crbug.com/785187 [ Linux ] virtual/mojo-loading/http/tests/devtools/elements/elements-panel-rewrite-href.js [ Failure Pass ]
-crbug.com/785187 [ Mac ] http/tests/devtools/elements/elements-panel-rewrite-href.js [ Failure Pass ]
 crbug.com/785662 [ Debug ] http/tests/devtools/sources/debugger-ui/reveal-not-skipped.js [ Failure Pass ]
 crbug.com/785662 [ Debug ] virtual/mojo-loading/http/tests/devtools/sources/debugger-ui/reveal-not-skipped.js [ Failure Pass ]
 
+# Flaky DevTools
+crbug.com/667560 http/tests/devtools/elements/elements-panel-rewrite-href.js [ Failure Pass ]
+crbug.com/667560 virtual/mojo-loading/http/tests/devtools/elements/elements-panel-rewrite-href.js [ Failure Pass ]
+
 # Sheriff failures 2017-11-16
 crbug.com/785980 [ Win10 ] virtual/mojo-loading/http/tests/devtools/network/network-xhr-same-url-as-main-resource.js [ Failure Pass ]
 crbug.com/785980 [ Win10 ] http/tests/devtools/network/network-xhr-same-url-as-main-resource.js [ Failure Pass ]