Mark editing/pasteboard/drag-drop-iframe-refresh-crash.html as leaky

TBR=yosin@chromium.org
NOTRY=true

BUG: 860117
Change-Id: Ibcb6d72b0bdefa2f4538cb9b04ee753840c804b7
Reviewed-on: https://chromium-review.googlesource.com/1125545Reviewed-by: Makoto Shimazu <shimazu@chromium.org>
Commit-Queue: Makoto Shimazu <shimazu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#572464}

third_party/WebKit/LayoutTests/LeakExpectations

@@ -48,6 +48,8 @@ crbug.com/780386 external/wpt/html/dom/reflection-grouping.html [ Leak Pass ]
 crbug.com/667560 [ Linux ] http/tests/devtools/console/console-search.js [ Leak Pass ]
 crbug.com/835943 [ Linux ] http/tests/appcache/non-html.xhtml [ Leak Pass ]
 
+crbug.com/860117 [ Linux ] editing/pasteboard/drag-drop-iframe-refresh-crash.html [ Pass Leak ]
+
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 # Not revert suspected CL as jam@ request, expected to be fixed soon.
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