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

    <EditText
        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:textColor="@color/default_text_color"
        android:textSize="16sp" />

    <org.chromium.chrome.browser.widget.TintedImageButton
        android:id="@+id/clear_text_button"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:paddingStart="16dp"
        android:paddingEnd="12dp"
        android:src="@drawable/btn_delete_url"
        android:background="@null"
        android:scaleType="center"
        android:contentDescription="@string/accessibility_toolbar_btn_delete_url"
        android:visibility="invisible"
        chrome:chrometint="@color/dark_mode_tint" />
</LinearLayout>