[DO NOT MERGE] Prevent hotseat touch hijack

Currently in AllAppsContinerView#onInterceptTouchEvent we check if a
touch event is in bounds of RecyclerViewFastScroller and set
mTouchHandler so the scroll bar handles onTouchEvent. However, if a user
performs a back gesture from the right side (which overlaps with the
scroller) and returns home, touches to the hotseat get intercepted.

Bug: 148639821
Test: Manual
Change-Id: Ie44f3a16b628b12ad00a7ae6c6bc5703171fbb56

src/com/android/launcher3/allapps/AllAppsContainerView.java

@@ -26,14 +26,18 @@ import android.os.Process;
 import android.text.Selection;
 import android.text.SpannableStringBuilder;
 import android.util.AttributeSet;
-import android.util.Log;
 import android.view.KeyEvent;
 import android.view.LayoutInflater;
 import android.view.MotionEvent;
 import android.view.View;
 import android.view.ViewGroup;
 import android.view.WindowInsets;
-
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.annotation.StringRes;
+import androidx.dynamicanimation.animation.DynamicAnimation;
+import androidx.recyclerview.widget.LinearLayoutManager;
+import androidx.recyclerview.widget.RecyclerView;
 import com.android.launcher3.AppInfo;
 import com.android.launcher3.DeviceProfile;
 import com.android.launcher3.DeviceProfile.OnDeviceProfileChangeListener;
@@ -45,11 +49,11 @@ import com.android.launcher3.ItemInfo;
 import com.android.launcher3.Launcher;
 import com.android.launcher3.LauncherState;
 import com.android.launcher3.R;
-import com.android.launcher3.testing.TestProtocol;
 import com.android.launcher3.Utilities;
 import com.android.launcher3.compat.AccessibilityManagerCompat;
 import com.android.launcher3.config.FeatureFlags;
 import com.android.launcher3.keyboard.FocusedItemDecorator;
+import com.android.launcher3.testing.TestProtocol;
 import com.android.launcher3.userevent.nano.LauncherLogProto.ContainerType;
 import com.android.launcher3.userevent.nano.LauncherLogProto.Target;
 import com.android.launcher3.util.ItemInfoMatcher;
@@ -60,13 +64,6 @@ import com.android.launcher3.views.BottomUserEducationView;
 import com.android.launcher3.views.RecyclerViewFastScroller;
 import com.android.launcher3.views.SpringRelativeLayout;
 
-import androidx.annotation.NonNull;
-import androidx.annotation.Nullable;
-import androidx.annotation.StringRes;
-import androidx.dynamicanimation.animation.DynamicAnimation;
-import androidx.recyclerview.widget.LinearLayoutManager;
-import androidx.recyclerview.widget.RecyclerView;
-
 /**
  * The all apps view container.
  */
@@ -200,7 +197,10 @@ public class AllAppsContainerView extends SpringRelativeLayout implements DragSo
 
         // The AllAppsContainerView houses the QSB and is hence visible from the Workspace
         // Overview states. We shouldn't intercept for the scrubber in these cases.
-        if (!mLauncher.isInState(LauncherState.ALL_APPS)) return false;
+        if (!mLauncher.isInState(LauncherState.ALL_APPS)) {
+            mTouchHandler = null;
+            return false;
+        }
 
         if (ev.getAction() == MotionEvent.ACTION_DOWN) {
             AllAppsRecyclerView rv = getActiveRecyclerView();
@@ -219,6 +219,16 @@ public class AllAppsContainerView extends SpringRelativeLayout implements DragSo
 
     @Override
     public boolean onTouchEvent(MotionEvent ev) {
+        if (ev.getAction() == MotionEvent.ACTION_DOWN) {
+            AllAppsRecyclerView rv = getActiveRecyclerView();
+            if (rv != null && rv.getScrollbar()
+                .isHitInParent(ev.getX(), ev.getY(), mFastScrollerOffset)) {
+                mTouchHandler = rv.getScrollbar();
+            } else {
+                mTouchHandler = null;
+            }
+        }
+
         if (mTouchHandler != null) {
             mTouchHandler.handleTouchEvent(ev, mFastScrollerOffset);
             return true;