Inherit default text color from MainTheme.

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

 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright 2016 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. -->
 
 <!-- Represents a single item in the DownloadHistoryAdapterView. --> 
 <view class="org.chromium.chrome.browser.download.ui.DownloadItemView"
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="wrap_content"
     android:layout_height="wrap_content" >
@@ skipping 20 matching lines @@
                 android:background="@color/light_active_color" />
 
         <TextView
                 android:id="@+id/filename_view"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:layout_alignParentTop="true"
                 android:layout_alignParentEnd="true"
                 android:layout_toEndOf="@+id/icon_view"
                 android:singleLine="true"
-                android:textColor="@color/default_text_color"
                 android:textSize="16sp" />
 
         <TextView
                 android:id="@+id/hostname_view"
                 android:layout_width="0dp"
                 android:layout_height="wrap_content"
                 android:layout_alignParentBottom="true"
                 android:layout_toEndOf="@+id/icon_view"
                 android:layout_toStartOf="@+id/filesize_view"
                 android:layout_below="@+id/filename_view"
@@ skipping 11 matching lines @@
                 android:layout_alignParentBottom="true"
                 android:layout_alignParentEnd="true"
                 android:layout_below="@+id/filename_view"
                 android:layout_marginTop="0dp"
                 android:textAlignment="viewEnd"
                 android:textColor="@color/google_grey_600"
                 android:singleLine="true" />
     </RelativeLayout>
 
  </view>