Revert "Make horizontal scrolling visible on diff page"

This reverts commit 52c943d88e088894e61e054964ec91ffe410a0bc.

Change-Id: I63f4aa2efd386300c070521c5bccf1c6ac5c594e
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 e500da0..0816501 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html
@@ -44,6 +44,7 @@
         border-top: 1px solid #eee;
         display: flex;
         font: 12px var(--monospace-font-family);
+        overflow-x: auto;
         will-change: transform;
       }
       table {