ui_touch_selection_unittests.isolate: Don't bundle osmesa on Win and Mac.

The build target doesn't depend on it, so there's a chance that the file doesn't
exist yet when the isolate step runs.  Since it kind of looks like this is only
here due to a copy-paste error, removing the file from the isolate rather than
adding a dependency.

BUG=98637

Review URL: https://codereview.chromium.org/880573002

Cr-Commit-Position: refs/heads/master@{#313293}
1 file changed