[DO NOT MERGE] Adds fling gesture suppression to Launcher

Test: Tested locally
BUG: 150688842
Change-Id: Ifa96bd01363de47cf1d8cdce34d81d525c8c2c04
(cherry picked from commit 9b90b1b034)

quickstep/src/com/android/quickstep/OverviewComponentObserver.java

@@ -22,6 +22,7 @@ import static android.content.Intent.ACTION_PACKAGE_REMOVED;
 
 import static com.android.launcher3.util.PackageManagerHelper.getPackageFilter;
 import static com.android.systemui.shared.system.PackageManagerWrapper.ACTION_PREFERRED_ACTIVITY_CHANGED;
+import static com.android.systemui.shared.system.QuickStepContract.SYSUI_STATE_ASSIST_GESTURE_CONSTRAINED;
 import static com.android.systemui.shared.system.QuickStepContract.SYSUI_STATE_HOME_DISABLED;
 
 import android.content.BroadcastReceiver;
@@ -107,6 +108,10 @@ public final class OverviewComponentObserver {
         }
     }
 
+    public boolean assistantGestureIsConstrained() {
+        return (mSystemUiStateFlags & SYSUI_STATE_ASSIST_GESTURE_CONSTRAINED) != 0;
+    }
+
     /**
      * Update overview intent and {@link ActivityControlHelper} based off the current launcher home
      * component.