Revert of Making answer card to behave like other results.

ui/views/controls/webview/web_contents_set_background_color.cc

Index: ui/views/controls/webview/web_contents_set_background_color.cc
diff --git a/ui/views/controls/webview/web_contents_set_background_color.cc b/ui/views/controls/webview/web_contents_set_background_color.cc
deleted file mode 100644
index e5de0e42b34b57ec669f1c94501375e55e1d4913..0000000000000000000000000000000000000000
--- a/ui/views/controls/webview/web_contents_set_background_color.cc
+++ /dev/null
@@ -1,57 +0,0 @@
-// Copyright 2017 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "ui/views/controls/webview/web_contents_set_background_color.h"
-
-#include "base/memory/ptr_util.h"
-#include "content/public/browser/render_view_host.h"
-#include "content/public/browser/render_widget_host.h"
-#include "content/public/browser/render_widget_host_view.h"
-
-DEFINE_WEB_CONTENTS_USER_DATA_KEY(views::WebContentsSetBackgroundColor);
-
-namespace views {
-
-// static
-void WebContentsSetBackgroundColor::CreateForWebContentsWithColor(
-    content::WebContents* web_contents,
-    SkColor color) {
-  if (FromWebContents(web_contents))
-    return;
-
-  // SupportsUserData::Data takes ownership over the
-  // WebContentsSetBackgroundColor instance and will destroy it when the
-  // WebContents instance is destroyed.
-  web_contents->SetUserData(
-      UserDataKey(),
-      base::WrapUnique(new WebContentsSetBackgroundColor(web_contents, color)));
-}
-
-WebContentsSetBackgroundColor::WebContentsSetBackgroundColor(
-    content::WebContents* web_contents,
-    SkColor color)
-    : content::WebContentsObserver(web_contents), color_(color) {}
-
-WebContentsSetBackgroundColor::~WebContentsSetBackgroundColor() {}
-
-void WebContentsSetBackgroundColor::RenderViewReady() {
-  web_contents()
-      ->GetRenderViewHost()
-      ->GetWidget()
-      ->GetView()
-      ->SetBackgroundColor(color_);
-}
-
-void WebContentsSetBackgroundColor::RenderViewCreated(
-    content::RenderViewHost* render_view_host) {
-  render_view_host->GetWidget()->GetView()->SetBackgroundColor(color_);
-}
-
-void WebContentsSetBackgroundColor::RenderViewHostChanged(
-    content::RenderViewHost* old_host,
-    content::RenderViewHost* new_host) {
-  new_host->GetWidget()->GetView()->SetBackgroundColor(color_);
-}
-
-}  // namespace views