Inherit default text color from MainTheme.

chrome/android/java/res/values-v17/styles.xml

 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright 2014 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. -->
 
 <resources xmlns:tools="http://schemas.android.com/tools">
     <!-- Q: Why put style resources under values-v17/ ?
          A: Problem:
             1. paddingStart causes a crash on Galaxy Tab&Note b/8351339.
             2. So we wrote a build script(generate_v14_compatible_resources.py) to convert
                paddingStart to paddingLeft for pre-v17 (crbug.com/235118).
             3. However, style files are not overrided by the corresponding generated style files,
                but merged when we pass them to aapt unlike layout files.
 
             So we decided to keep style resources under values-v17/ so that it is not merged with
             the generated style resources under res_v14_compatibility/values/ (crbug.com/243952).
     -->
 
     <style name="LauncherTheme" parent="@android:style/Theme.NoDisplay" />
 
     <style name="MainTheme" parent="Theme.AppCompat.Light.NoActionBar">
         <item name="android:windowContentOverlay">@null</item>
         <item name="android:textColorHighlight">@color/text_highlight_color</item>
         <item name="android:textColorLink">@color/light_active_color</item>
         <item name="android:statusBarColor" tools:targetApi="21">@android:color/black</item>
+        <item name="android:textColor">@color/default_text_color</item>

[gone, 2016/10/07 21:42:17]

This impacts every bit of text everywhere that is inheriting from Android's
default theme and not explicitly setting default_text_color themselves.

 
         <!--  Overriding AppCompat values -->
         <item name="colorControlNormal">@color/light_normal_color</item>
         <item name="colorControlActivated">@color/light_active_color</item>
 
         <!-- Default TintedImageButton tint -->
         <item name="tint">@color/dark_mode_tint</item>
 
         <!-- Navigation Transitions, requires API level 21 -->
         <item name="android:windowAllowEnterTransitionOverlap" tools:targetApi="21">false</item>
@@ skipping 12 matching lines @@
     <style name="FullscreenWhiteDialog" parent="Theme.AppCompat.Light" >
         <item name="android:windowBackground">@android:color/white</item>
         <item name="android:textColorLink">@color/light_active_color</item>
         <item name="android:statusBarColor" tools:targetApi="21">@android:color/black</item>
         <item name="colorPrimary">@color/light_active_color</item>
         <item name="colorAccent">@color/light_active_color</item>
     </style>
 
     <style name="DownloadActivityTheme" parent="FullscreenWhiteDialog">
         <item name="colorPrimaryDark">@android:color/black</item>
+        <item name="android:textColor">@color/default_text_color</item>
 
         <!-- Remove ActionBar -->
         <item name="windowNoTitle">true</item>
         <item name="windowActionBar">false</item>
     </style>
 
     <!-- Web app themes -->
     <style name="WebappTheme" parent="MainTheme">
         <item name="android:windowBackground">@null</item>
         <item name="android:windowDisablePreview">true</item>
@@ skipping 514 matching lines @@
     </style>
     <style name="MaterialProgressBar" parent="Widget.AppCompat.ProgressBar.Horizontal">
         <item name="android:progressDrawable">@drawable/material_progressbar</item>
     </style>
 
     <!-- New tab page RecyclerView overscroll color -->
     <style name="NewTabPageRecyclerView">
         <item name="android:colorEdgeEffect">@color/google_grey_300</item>
     </style>
 </resources>