[Offline pages, NTP] Unifying offline_pin_round(_black) icon

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

 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright 2015 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. -->
 
 <RelativeLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:chrome="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:id="@+id/snippets_card_view"
@@ skipping 52 matching lines @@
 
         <!-- We can't add this ImageView as a CompoundDrawable to the TextView because we want to
         have different paddings between the favicon (which is a compound drawable on the TextView)
         and the offline icon. -->
         <ImageView
             android:id="@+id/offline_icon"
             android:layout_width="@dimen/snippets_offline_icon_size"
             android:layout_height="@dimen/snippets_offline_icon_size"
             android:layout_marginStart="6dp"
             android:alpha="0.46"
-            android:src="@drawable/offline_pin_black"
+            android:src="@drawable/offline_pin_round"
             android:contentDescription="@string/accessibility_ntp_offline_badge"
             android:visibility="gone" />
 
     </LinearLayout>
 
     <ImageView
         android:id="@+id/article_thumbnail"
         android:background="@color/snippets_thumnail_placeholder_bg"
         android:layout_width="@dimen/snippets_thumbnail_size"
         android:layout_height="@dimen/snippets_thumbnail_size"
         android:layout_alignParentTop="true"
         android:layout_alignParentEnd="true"
         android:layout_marginStart="16dp"
         android:scaleType="centerCrop"
         android:contentDescription="@null"
         android:src="@null" />
 </RelativeLayout>