Connect split-screen things to systemui divider

Since divider stuff lives in sysui instead of framework

Bug: 133381284
Test: Manual, open 2 apps in split and drag-up to show
      recents.
Change-Id: If6740b7ee4829bf4cac6e829e81943f16a41f977

quickstep/src/com/android/quickstep/RecentsAnimationController.java

@@ -81,12 +81,9 @@ public class RecentsAnimationController {
             mWindowThresholdCrossed = windowThresholdCrossed;
             UI_HELPER_EXECUTOR.execute(() -> {
                 mController.setAnimationTargetsBehindSystemBars(!windowThresholdCrossed);
-                if (mShouldMinimizeSplitScreen && windowThresholdCrossed) {
-                    // NOTE: As a workaround for conflicting animations (Launcher animating the task
-                    // leash, and SystemUI resizing the docked stack, which resizes the task), we
-                    // currently only set the minimized mode, and not the inverse.
-                    // TODO: Synchronize the minimize animation with the launcher animation
-                    mController.setSplitScreenMinimized(windowThresholdCrossed);
+                SystemUiProxy p = SystemUiProxy.INSTANCE.getNoCreate();
+                if (p != null && mShouldMinimizeSplitScreen) {
+                    p.setSplitScreenMinimized(windowThresholdCrossed);
                 }
             });
         }

quickstep/src/com/android/quickstep/SystemUiProxy.java

@@ -296,4 +296,15 @@ public class SystemUiProxy implements ISystemUiProxy {
             }
         }
     }
+
+    @Override
+    public void setSplitScreenMinimized(boolean minimized) {
+        if (mSystemUiProxy != null) {
+            try {
+                mSystemUiProxy.setSplitScreenMinimized(minimized);
+            } catch (RemoteException e) {
+                Log.w(TAG, "Failed call stopScreenPinning", e);
+            }
+        }
+    }
 }