[Fixit] Fix Recents icon

The app icon in Recents was appearing with an outline because we were
calling Actvity#setTaskDescription() to fix an issue where the Recents
item header in older versions of Android would have a colorPrimary
background. The reason was that we were providing R.mipmap.app_icon with
the call, which resolves to the app icon that should only be used
below API 26.

This CL passes null for values in the TaskDescription that we don't
intend to change.

Bug: 1220734
Change-Id: I4b3567b85019e0a65ae83699e319c5d1066d2d8d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4159812
Reviewed-by: Theresa Sullivan <twellington@chromium.org>
Commit-Queue: Sinan Sahin <sinansahin@google.com>
Cr-Commit-Position: refs/heads/main@{#1091635}
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ChromeBaseAppCompatActivity.java b/chrome/android/java/src/org/chromium/chrome/browser/ChromeBaseAppCompatActivity.java
index 3bbeccc..42711d36 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ChromeBaseAppCompatActivity.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ChromeBaseAppCompatActivity.java
@@ -10,8 +10,6 @@
 import android.content.Context;
 import android.content.SharedPreferences;
 import android.content.res.Configuration;
-import android.content.res.Resources;
-import android.graphics.BitmapFactory;
 import android.os.Build;
 import android.os.Bundle;
 
@@ -257,11 +255,8 @@
      * Sets the default task description that will appear in the recents UI.
      */
     protected void setDefaultTaskDescription() {
-        final Resources res = getResources();
         final TaskDescription taskDescription =
-                new TaskDescription(res.getString(R.string.app_name),
-                        BitmapFactory.decodeResource(res, R.mipmap.app_icon),
-                        res.getColor(R.color.default_task_description_color));
+                new TaskDescription(null, null, getColor(R.color.default_task_description_color));
         setTaskDescription(taskDescription);
     }