res/layout/conversation_view.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
     Copyright (C) 2011 Google Inc.
     Licensed to The Android Open Source Project.

     Licensed under the Apache License, Version 2.0 (the "License");
     you may not use this file except in compliance with the License.
     You may obtain a copy of the License at

          http://www.apache.org/licenses/LICENSE-2.0

     Unless required by applicable law or agreed to in writing, software
     distributed under the License is distributed on an "AS IS" BASIS,
     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     See the License for the specific language governing permissions and
     limitations under the License.
-->
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.android.mail.browse.ConversationContainer
        android:id="@+id/conversation_container"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <!-- base WebView layer -->
        <com.android.mail.browse.ConversationWebView
            android:id="@+id/conversation_webview"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:focusable="false"
            android:focusableInTouchMode="false"
            android:scrollbars="none"
            style="@style/ConversationViewPaddingStyle" />

        <!-- scrolling overlay views go here -->

        <!-- topmost layer for floating views (e.g. snap header, New Message bar) -->
        <!-- ConversationContainer draws this child on the very top, above all scrolling views -->
        <!-- This is also used to highlight the entire conversation on focus -->
        <FrameLayout
            android:id="@+id/conversation_topmost_overlay"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:background="?android:attr/selectableItemBackground"
            android:focusable="true" />

    </com.android.mail.browse.ConversationContainer>

    <com.android.mail.browse.ScrollIndicatorsView
        android:id="@+id/scroll_indicators"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:scrollbarStyle="outsideOverlay"
        android:scrollbars="vertical|horizontal" />

    <include layout="@layout/conversation_load_spinner"/>

</FrameLayout>