Add recent tasks to Taskbar

- Also adds a divider between Hotseat and Recents
- Dedupes Recents from Hotseat

Test: Open some recent tasks, ensure they are deduped
from Hotseat and also handle < 2 tasks.

Bug: 171917176
Change-Id: Ia782c6ccbcda94cfd844aad04dc3d25a3f072c2b
diff --git a/quickstep/res/layout/taskbar_divider.xml b/quickstep/res/layout/taskbar_divider.xml
new file mode 100644
index 0000000..6e1aa1e
--- /dev/null
+++ b/quickstep/res/layout/taskbar_divider.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2021 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.
+-->
+
+<View
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="@dimen/taskbar_divider_thickness"
+    android:layout_height="@dimen/taskbar_divider_height"
+    android:layout_marginStart="@dimen/taskbar_icon_spacing"
+    android:layout_marginEnd="@dimen/taskbar_icon_spacing"
+    android:background="@color/taskbar_divider" />
\ No newline at end of file