Fixed the clipping of the keyguard status bar during drag down

It wasn't clipped at all, but now it is.

Bug: 184946919
Test: drag down on lockscreen, observe no cliping
Change-Id: I13ad278898d76bdd364bbfb3c7e8d599b21bcdae

packages/SystemUI/src/com/android/systemui/statusbar/phone/KeyguardStatusBarView.java

@@ -116,6 +116,12 @@ public class KeyguardStatusBarView extends RelativeLayout implements
     // right and left padding applied to this view to account for cutouts and rounded corners
     private Pair<Integer, Integer> mPadding = new Pair(0, 0);
 
+    /**
+     * The clipping on the top
+     */
+    private int mTopClipping;
+    private final Rect mClipRect = new Rect(0, 0, 0, 0);
+
     public KeyguardStatusBarView(Context context, AttributeSet attrs) {
         super(context, attrs);
         mUserManager = UserManager.get(getContext());
@@ -549,4 +555,25 @@ public class KeyguardStatusBarView extends RelativeLayout implements
     public void onSystemChromeAnimationUpdate(ValueAnimator anim) {
         mSystemIconsContainer.setAlpha((float) anim.getAnimatedValue());
     }
+
+    @Override
+    protected void onLayout(boolean changed, int l, int t, int r, int b) {
+        super.onLayout(changed, l, t, r, b);
+        updateClipping();
+    }
+
+    /**
+     * Set the clipping on the top of the view.
+     */
+    public void setTopClipping(int topClipping) {
+        if (topClipping != mTopClipping) {
+            mTopClipping = topClipping;
+            updateClipping();
+        }
+    }
+
+    private void updateClipping() {
+        mClipRect.set(0, mTopClipping, getWidth(), getHeight());
+        setClipBounds(mClipRect);
+    }
 }

packages/SystemUI/src/com/android/systemui/statusbar/phone/NotificationPanelViewController.java

@@ -2235,6 +2235,7 @@ public class NotificationPanelViewController extends PanelViewController {
             boolean visible) {
         // Fancy clipping for quick settings
         int radius = mScrimCornerRadius;
+        int statusBarClipTop = 0;
         if (!mShouldUseSplitNotificationShade) {
             // The padding on this area is large enough that we can use a cheaper clipping strategy
             mKeyguardStatusAreaClipBounds.set(left, top, right, bottom);
@@ -2242,12 +2243,14 @@ public class NotificationPanelViewController extends PanelViewController {
                     ? mKeyguardStatusAreaClipBounds : null);
             radius = (int) MathUtils.lerp(mScreenCornerRadius, mScrimCornerRadius,
                     Math.min(top / (float) mScrimCornerRadius, 1f));
+            statusBarClipTop = top - mKeyguardStatusBar.getTop();
         }
         if (mQs != null) {
             mQs.setFancyClipping(top, bottom, radius, visible);
         }
         mScrimController.setNotificationsBounds(left, top, right, bottom);
         mScrimController.setScrimCornerRadius(radius);
+        mKeyguardStatusBar.setTopClipping(statusBarClipTop);
     }
 
     private float getQSEdgePosition() {