Improve page scrolling performance part 3

Remove unnecessary overlay: hidden from diff content, since the diff
lines now are allowed to expand beyond char limit to accommodate fonts
with variable width cars (e.g. CJK).

Bug: Issue 8825
Change-Id: I1326b317ec986ee9ed19c59ac6ca5b4e7e79eb82
diff --git a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html
index 81c6d99..540df98 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html
@@ -108,7 +108,6 @@
         cursor: pointer;
       }
       .content {
-        overflow: hidden;
         /* Set min width since setting width on table cells still
            allows them to shrink. Do not set max width because
            CJK (Chinese-Japanese-Korean) glyphs have variable width */