Remove `GroupTask.mSplitBounds`

See go/refactor-group-task for details. This CL removes `mSplitBounds`
from `GroupTask` and adds `splitBounds` to `SplitTask`. This makes its
usages more intentional.

Bug: 388593902
Test: m
Flag: EXEMPT pure refactor with no behavior change.
Change-Id: I9a3e8ee2e96d46f9eb79a58ffcf5efc257615aac
diff --git a/quickstep/src/com/android/launcher3/taskbar/KeyboardQuickSwitchView.java b/quickstep/src/com/android/launcher3/taskbar/KeyboardQuickSwitchView.java
index 73f9bea..4581119 100644
--- a/quickstep/src/com/android/launcher3/taskbar/KeyboardQuickSwitchView.java
+++ b/quickstep/src/com/android/launcher3/taskbar/KeyboardQuickSwitchView.java
@@ -275,7 +275,7 @@
                     task2,
                     updateTasks ? mViewCallbacks::updateThumbnailInBackground : null,
                     updateTasks ? mViewCallbacks::updateIconInBackground : null,
-                    groupTask.mSplitBounds);
+                    groupTask instanceof SplitTask splitTask ? splitTask.getSplitBounds() : null);
 
             previousTaskView = currentTaskView;
         }
diff --git a/quickstep/src/com/android/launcher3/uioverrides/QuickstepLauncher.java b/quickstep/src/com/android/launcher3/uioverrides/QuickstepLauncher.java
index c880aa9..690dec4 100644
--- a/quickstep/src/com/android/launcher3/uioverrides/QuickstepLauncher.java
+++ b/quickstep/src/com/android/launcher3/uioverrides/QuickstepLauncher.java
@@ -65,7 +65,6 @@
 import static com.android.quickstep.util.AnimUtils.completeRunnableListCallback;
 import static com.android.quickstep.util.SplitAnimationTimings.TABLET_HOME_TO_SPLIT;
 import static com.android.systemui.shared.system.ActivityManagerWrapper.CLOSE_SYSTEM_WINDOWS_REASON_HOME_KEY;
-import static com.android.wm.shell.shared.split.SplitScreenConstants.SNAP_TO_2_50_50;
 
 import android.animation.Animator;
 import android.animation.AnimatorListenerAdapter;
@@ -1390,16 +1389,13 @@
      */
     public void launchSplitTasks(
             @NonNull SplitTask splitTask, @Nullable RemoteTransition remoteTransition) {
-        mSplitSelectStateController.launchExistingSplitPair(
-                null /* launchingTaskView */,
+        mSplitSelectStateController.launchExistingSplitPair(null /* launchingTaskView */,
                 splitTask.getTopLeftTask().key.id,
                 splitTask.getBottomRightTask().key.id,
                 SplitConfigurationOptions.STAGE_POSITION_TOP_OR_LEFT,
                 /* callback= */ success -> mSplitSelectStateController.resetState(),
                 /* freezeTaskList= */ false,
-                splitTask.mSplitBounds == null
-                        ? SNAP_TO_2_50_50
-                        : splitTask.mSplitBounds.snapPosition,
+                splitTask.getSplitBounds().snapPosition,
                 remoteTransition);
     }
 
diff --git a/quickstep/src/com/android/quickstep/util/DesktopTask.kt b/quickstep/src/com/android/quickstep/util/DesktopTask.kt
index 0669185..5d61dd4 100644
--- a/quickstep/src/com/android/quickstep/util/DesktopTask.kt
+++ b/quickstep/src/com/android/quickstep/util/DesktopTask.kt
@@ -23,7 +23,7 @@
  * tasks list.
  */
 class DesktopTask(override val tasks: List<Task>) :
-    GroupTask(tasks[0], null, null, TaskViewType.DESKTOP) {
+    GroupTask(tasks[0], task2 = null, TaskViewType.DESKTOP) {
 
     override fun containsTask(taskId: Int) = tasks.any { it.key.id == taskId }
 
diff --git a/quickstep/src/com/android/quickstep/util/GroupTask.kt b/quickstep/src/com/android/quickstep/util/GroupTask.kt
index 8237d2e..9ab9633 100644
--- a/quickstep/src/com/android/quickstep/util/GroupTask.kt
+++ b/quickstep/src/com/android/quickstep/util/GroupTask.kt
@@ -30,19 +30,12 @@
 constructor(
     @Deprecated("Prefer using `getTasks()` instead") @JvmField val task1: Task,
     @Deprecated("Prefer using `getTasks()` instead") @JvmField val task2: Task?,
-    @JvmField val mSplitBounds: SplitConfigurationOptions.SplitBounds?,
     @JvmField val taskViewType: TaskViewType,
 ) {
     protected constructor(
         task1: Task,
         task2: Task?,
-        splitBounds: SplitConfigurationOptions.SplitBounds?,
-    ) : this(
-        task1,
-        task2,
-        splitBounds,
-        if (task2 != null) TaskViewType.GROUPED else TaskViewType.SINGLE,
-    )
+    ) : this(task1, task2, if (task2 != null) TaskViewType.GROUPED else TaskViewType.SINGLE)
 
     open fun containsTask(taskId: Int) =
         task1.key.id == taskId || (task2 != null && task2.key.id == taskId)
@@ -83,8 +76,7 @@
 }
 
 /** A [Task] container that must contain exactly one task in the recent tasks list. */
-class SingleTask(task: Task) :
-    GroupTask(task, task2 = null, mSplitBounds = null, TaskViewType.SINGLE) {
+class SingleTask(task: Task) : GroupTask(task, task2 = null, TaskViewType.SINGLE) {
 
     val task: Task
         get() = task1
@@ -104,25 +96,25 @@
  * A [Task] container that must contain exactly two tasks and split bounds to represent an app-pair
  * in the recent tasks list.
  */
-class SplitTask(task1: Task, task2: Task, splitBounds: SplitConfigurationOptions.SplitBounds) :
-    GroupTask(task1, task2, splitBounds, TaskViewType.GROUPED) {
+class SplitTask(task1: Task, task2: Task, val splitBounds: SplitConfigurationOptions.SplitBounds) :
+    GroupTask(task1, task2, TaskViewType.GROUPED) {
 
     val topLeftTask: Task
-        get() = if (mSplitBounds!!.leftTopTaskId == task1.key.id) task1!! else task2!!
+        get() = if (splitBounds.leftTopTaskId == task1.key.id) task1!! else task2!!
 
     val bottomRightTask: Task
         get() = if (topLeftTask == task1) task2!! else task1!!
 
-    override fun copy() = SplitTask(task1, task2!!, mSplitBounds!!)
+    override fun copy() = SplitTask(task1, task2!!, splitBounds)
 
     override fun toString() = "type=$taskViewType task1=$task1 task2=$task2"
 
     override fun equals(o: Any?): Boolean {
         if (this === o) return true
         if (o !is SplitTask) return false
-        if (mSplitBounds!! != o.mSplitBounds!!) return false
+        if (splitBounds != o.splitBounds) return false
         return super.equals(o)
     }
 
-    override fun hashCode() = Objects.hash(super.hashCode(), mSplitBounds)
+    override fun hashCode() = Objects.hash(super.hashCode(), splitBounds)
 }
diff --git a/quickstep/src/com/android/quickstep/views/RecentsView.java b/quickstep/src/com/android/quickstep/views/RecentsView.java
index c6db576..5e59a06 100644
--- a/quickstep/src/com/android/quickstep/views/RecentsView.java
+++ b/quickstep/src/com/android/quickstep/views/RecentsView.java
@@ -1988,7 +1988,7 @@
                 var splitTask = (SplitTask) groupTask;
                 groupedTaskView.bind(splitTask.getTopLeftTask(),
                         splitTask.getBottomRightTask(), mOrientationState,
-                        mTaskOverlayFactory, splitTask.mSplitBounds);
+                        mTaskOverlayFactory, splitTask.getSplitBounds());
             } else if (taskView instanceof DesktopTaskView desktopTaskView) {
                 // Minimized tasks should not be shown in Overview
                 List<Task> nonMinimizedTasks =