🔍 Introduce default search engine dialog

chrome/android/java/res/layout/promo_dialog_layout.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. -->
 
 <!-- This XML should not be inflated by anything except PromoDialog.java.
 
      This layout is deeply nested to account for the various bits having to flop orientations
      in landscape.  If these become more frequently used, we should investigate optimizing the
      layout.
 -->
 <merge xmlns:android="http://schemas.android.com/apk/res/android"
         xmlns:chrome="http://schemas.android.com/apk/res-auto" >
 
     <org.chromium.chrome.browser.widget.PromoDialogLayout
             android:id="@+id/promo_dialog_layout"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:layout_gravity="center"
             android:orientation="vertical"
             android:background="@drawable/menu_bg"
             chrome:maxWidth="@dimen/promo_dialog_max_width" >
 
         <org.chromium.chrome.browser.widget.FadingEdgeScrollView
                 android:id="@+id/promo_container"
                 android:layout_width="wrap_content"
                 android:layout_height="0dp"
-                android:layout_weight="1" >
+                android:layout_weight="1"
+                android:fadeScrollbars="false" >
 
             <!-- This layout pivots when the dialog is wider than it is tall. -->
             <LinearLayout
-                    android:id="@+id/promo_content"
+                    android:id="@+id/full_promo_content"
                     android:layout_width="wrap_content"
                     android:layout_height="wrap_content"
                     android:padding="@dimen/promo_dialog_padding"
                     android:gravity="center"
                     android:orientation="vertical" >
 
                 <ImageView
                         android:id="@+id/illustration"
                         android:layout_width="@dimen/promo_dialog_illustration_width"
                         android:layout_height="wrap_content"
                         android:layout_gravity="center"
-                        android:layout_margin="@dimen/promo_dialog_illustration_margin"
+                        android:layout_marginTop="@dimen/promo_dialog_illustration_margin"
+                        android:layout_marginStart="@dimen/promo_dialog_illustration_margin"
+                        android:layout_marginEnd="@dimen/promo_dialog_illustration_margin"
                         android:scaleType="fitCenter"
                         android:contentDescription="@null" />
 
                 <org.chromium.chrome.browser.widget.BoundedLinearLayout
+                        android:id="@+id/scrollable_promo_content"
                         android:layout_width="wrap_content"
                         android:layout_height="wrap_content"
                         android:orientation="vertical"
                         chrome:maxWidth="@dimen/promo_dialog_max_content_width" >
 
                     <TextView
                             android:id="@+id/header"
                             android:layout_width="wrap_content"
                             android:layout_height="wrap_content"
-                            android:layout_marginBottom="14dp"
+                            android:layout_marginTop="@dimen/dialog_header_margin"
+                            android:layout_marginBottom="@dimen/dialog_header_margin"
                             android:textColor="@color/default_text_color"
                             android:textSize="@dimen/promo_dialog_title_text_size" />
 
                     <TextView
                             android:id="@+id/subheader"
                             android:layout_width="wrap_content"
                             android:layout_height="wrap_content"
                             android:lineSpacingMultiplier="1.3"
                             android:textColor="#646464"
                             android:textSize="@dimen/promo_dialog_normal_text_size" />
                 </org.chromium.chrome.browser.widget.BoundedLinearLayout>
             </LinearLayout>
 
         </org.chromium.chrome.browser.widget.FadingEdgeScrollView>
 
+        <ViewStub
+                android:id="@+id/footer_stub"
+                android:layout="@layout/infobar_control_description"
+                android:inflatedId="@+id/footer"
+                android:layout_margin="@dimen/promo_dialog_padding"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content" />
+
         <org.chromium.chrome.browser.widget.DualControlLayout
                 android:id="@+id/button_bar"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:layout_gravity="end"
                 android:padding="@dimen/promo_dialog_padding"
                 chrome:buttonAlignment="end"
                 chrome:stackedMargin="@dimen/infobar_padding" />
 
     </org.chromium.chrome.browser.widget.PromoDialogLayout>
 
 </merge>