Add a time period dropdown to the CBD dialog on Android.

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

Index: chrome/android/java/res/layout/preference_spinner.xml
diff --git a/chrome/android/java/res/layout/preference_button.xml b/chrome/android/java/res/layout/preference_spinner.xml
similarity index 52%
copy from chrome/android/java/res/layout/preference_button.xml
copy to chrome/android/java/res/layout/preference_spinner.xml
index 5a18078488d36bbb643397d4368b53e6848f8000..f46042976cd09282f27bc500b983b6113b2398ea 100644
--- a/chrome/android/java/res/layout/preference_button.xml
+++ b/chrome/android/java/res/layout/preference_spinner.xml
@@ -1,9 +1,9 @@
 <?xml version="1.0" encoding="utf-8"?>
-<!-- Copyright 2014 The Chromium Authors. All rights reserved.
+<!-- 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. -->
 
-<!-- Layout used by ButtonPreference for the button widget style. -->
+<!-- Layout used by SpinnerPreference. -->
 
 <LinearLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
@@ -11,16 +11,18 @@
     style="@style/PreferenceLayout"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
-    android:clipToPadding="false"
-    android:gravity="center_vertical"
     android:orientation="vertical">
 
-    <org.chromium.ui.widget.ButtonCompat
-        android:id="@+id/button_preference"
+    <TextView
+        android:id="@+id/title"
         android:layout_height="wrap_content"
-        android:layout_width="wrap_content"
-        android:minHeight="40dp"
-        android:textColor="#fff"
-        chrome:buttonColor="@color/pref_accent_color" />
+        android:layout_width="match_parent" />
+
+    <Spinner
+        android:id="@+id/spinner"
+        android:layout_height="wrap_content"
+        android:layout_width="match_parent" />
+
+    <View style="@style/PreferenceSpinnerUnderlineView" />
 
 </LinearLayout>