Improve the "Learn more" link on the Incognito New Tab page.

chrome/android/java/res/layout/new_tab_page_incognito_md.xml

 <?xml version="1.0" encoding="utf-8"?>
 <!-- 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. -->
 
 <org.chromium.chrome.browser.ntp.IncognitoNewTabPageViewMD
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:chrome="http://schemas.android.com/apk/res-auto"
     android:id="@+id/ntp_content"
     android:layout_width="match_parent"
@@ skipping 62 matching lines @@
                   android:layout_height="wrap_content"
                   android:textColor="@color/incognito_text"
                   android:lineSpacingExtra="6sp" />
 
             </LinearLayout>
 
             <TextView
                 android:id="@+id/learn_more"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
-                android:background="?attr/listChoiceBackgroundIndicator"
                 android:clickable="true"
                 android:focusable="true"
                 android:text="@string/learn_more"
                 android:textColor="@color/google_blue_300"
-                android:lineSpacingExtra="6sp"
-                style="@style/RobotoMediumStyle" />
+                android:lineSpacingExtra="6sp" />
 
         </LinearLayout>
 
     </org.chromium.chrome.browser.ntp.NewTabPageScrollView>
 
 </org.chromium.chrome.browser.ntp.IncognitoNewTabPageViewMD>