Intersect task with stack bounds for dimming

Bug: 27240436
Change-Id: I9aba4a476d81b219e4d361d606a4339b0ebc5395
diff --git a/services/core/java/com/android/server/wm/Task.java b/services/core/java/com/android/server/wm/Task.java
index 4e8f19e..1f03c04 100644
--- a/services/core/java/com/android/server/wm/Task.java
+++ b/services/core/java/com/android/server/wm/Task.java
@@ -498,7 +498,15 @@
                 return;
             }
 
-            out.set(mBounds);
+            if (!mFullscreen) {
+                // When minimizing the docked stack when going home, we don't adjust the task bounds
+                // so we need to intersect the task bounds with the stack bounds here.
+                mStack.getBounds(mTmpRect);
+                mTmpRect.intersect(mBounds);
+                out.set(mTmpRect);
+            } else {
+                out.set(mBounds);
+            }
             return;
         }