Mark editing/caret/caret-is-hidden-when-no-focus.html flaky on win

TBR=wjmaclean@chromium.org
NOTRY=true

Bug: 875006
Change-Id: I84a6dfaee155b0cd241d4bc218af797071839859
Reviewed-on: https://chromium-review.googlesource.com/1178638Reviewed-by: Xida Chen <xidachen@chromium.org>
Commit-Queue: Xida Chen <xidachen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#583767}

third_party/WebKit/LayoutTests/TestExpectations

@@ -3926,6 +3926,7 @@ crbug.com/874567 [ Mac ] svg/custom/getscreenctm-in-scrollable-div-area-nested.x
 crbug.com/874837 [ Win ] ietestcenter/css3/bordersbackgrounds/background-attachment-local-scrolling.htm [ Pass Failure ]
 crbug.com/874866 [ Mac ] virtual/new-remote-playback-pipeline/media/controls/modern/doubletap-to-jump-backwards-at-start.html [ Pass Timeout ]
 crbug.com/874931 virtual/threaded/fast/scroll-behavior/smooth-scroll/mousewheel-scroll.html [ Pass Failure ]
+crbug.com/875003 [ Win ] editing/caret/caret-is-hidden-when-no-focus.html [ Pass Failure ]
 
 crbug.com/715718 external/wpt/media-source/mediasource-activesourcebuffers.html [ Failure Pass ]
 crbug.com/715718 external/wpt/media-source/mediasource-remove.html [ Failure Pass ]