Revert of [MD settings] hide extra horizontal scrollbar (patchset #1 id:20001...

Revert of [MD settings] hide extra horizontal scrollbar (patchset #1 id:20001 of https://codereview.chromium.org/2753943003/ )

Reason for revert:
The bug this is fixing
https://bugs.chromium.org/p/chromium/issues/detail?id=645346

Is not as bad as the bug it introduced
https://bugs.chromium.org/p/chromium/issues/detail?id=702496

Original issue's description:
> [MD settings] hide extra horizontal scrollbar
>
> This CL prevents an unwanted horizontal scrollbar from flashing at the
> bottom of the page when transitioning from a sub-page back to the basic
> page.
>
> BUG=645346
> CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation
>
> Review-Url: https://codereview.chromium.org/2753943003
> Cr-Commit-Position: refs/heads/master@{#457570}
> Committed: https://chromium.googlesource.com/chromium/src/+/bfa14e6ef0b8adc0f56d899f3776fe4b960b8978

TBR=dpapad@chromium.org,dschuyler@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=645346

Review-Url: https://codereview.chromium.org/2756253002
Cr-Commit-Position: refs/heads/master@{#457817}

chrome/browser/resources/settings/basic_page/basic_page.html

@@ -28,12 +28,6 @@
 <dom-module id="settings-basic-page">
   <template>
     <style include="settings-page-styles">
-      :host {
-        /* Prevent an unwanted horizontal scrollbar when transitioning back from
-         * a sub-page. */
-        overflow: hidden;
-      }
-
       #advancedToggle {
         --paper-button: {
           text-transform: none;