Add a ProgressDialog during sign-in flow when GMS is updated.

chrome/android/java/res/layout/account_signin_view.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.
 -->
 <org.chromium.chrome.browser.signin.AccountSigninView
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:chrome="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
@@ skipping 14 matching lines @@
             android:requiresFadingEdge="vertical"
             android:fadingEdgeLength="48dp">
 
             <LinearLayout
                 android:id="@+id/account_signin_choose_view_root_child_view"
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"
                 android:orientation="vertical">
 
                 <!-- The layout_width/layout_height is set to 16/9 dynamically in Java -->
-                <TextView 
+                <TextView
                     android:id="@+id/signin_title"
                     android:layout_width="match_parent"
                     android:layout_height="wrap_content"
                     android:gravity="bottom"
                     android:paddingStart="@dimen/signin_chooser_padding"
                     android:paddingEnd="@dimen/signin_chooser_padding"
                     android:paddingBottom="@dimen/signin_chooser_padding"
                     android:background="@color/signin_head_background"
                     android:textColor="@color/default_text_color"
                     android:textSize="@dimen/fre_title_text_size"
                     android:text="@string/sign_in_to_chrome"/>
 
-                <View 
+                <View
                     android:layout_width="match_parent"
                     android:layout_height="1dp"
                     android:background="@color/signin_border_line_color"
                     android:alpha="0.08"/>
 
-                <TextView 
+                <TextView
                     android:id="@+id/signin_choice_description"
                     android:layout_width="wrap_content"
                     android:layout_height="wrap_content"
                     android:padding="@dimen/signin_chooser_padding"
                     android:lineSpacingMultiplier="1.4"
                     android:text="@string/signin_account_choice_description"
                     android:textColor="@color/default_text_color"
                     android:textSize="@dimen/fre_normal_text_size"/>
             </LinearLayout>
         </org.chromium.chrome.browser.signin.AccountSigninChooseView>
@@ skipping 204 matching lines @@
 
         <View
             android:id="@+id/positive_button_end_padding"
             android:layout_width="0dp"
             android:layout_height="0dp"
             android:layout_weight="1"
             android:visibility="gone"/>
     </LinearLayout>
 
 </org.chromium.chrome.browser.signin.AccountSigninView>