chrome/android/java/res/layout/search_toolbar.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. -->

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/search_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="horizontal"
    android:visibility="gone" >

    <!-- TODO(crbug.com/900912): Fix and remove lint ignore -->
    <EditText
        tools:ignore="Autofill,LabelFor"
        android:id="@+id/search_text"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:background="@null"
        android:imeOptions="flagNoExtractUi|actionSearch"
        android:inputType="text"
        android:singleLine="true"
        android:textAppearance="@style/TextAppearance.BlackTitle1"
        android:textColorHint="@color/search_box_hint"/>

    <org.chromium.ui.widget.ChromeImageButton
        android:id="@+id/clear_text_button"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:paddingStart="16dp"
        android:paddingEnd="@dimen/clear_text_button_end_padding"
        android:src="@drawable/btn_delete_24dp"
        android:background="@null"
        android:scaleType="center"
        android:contentDescription="@string/accessibility_toolbar_btn_delete_url"
        android:visibility="invisible"
        app:tint="@color/standard_mode_tint" />
</LinearLayout>