Disabled accessibility browser test for content editable descendents.
Required in order to reland CL
1056763002. The only difference in the test output is that on the Mac the textual contents of the contenteditable are also present in the AXValue property on the AXGroup representing the contenteditable. I prefer to reland the contenteditable CL in order to investigate this more easily on my Mac.
BUG=347859
R=dmazzoni
Review URL: https://codereview.chromium.org/
1080533004
Cr-Commit-Position: refs/heads/master@{#325452}