Remove the unnecessary warning log

While cold-start an activity, a root task was created and
the activity type was set before adding the root task to TDA.
Therefore, the configuration needs to be updated and checked
for multi-window mode support. So, the warning log was dumped
since the root task was not added to TDA yet.

Bug: 163976519
Test: cold start an activity
Change-Id: I12f9167263939d760dabdd1098404fa9fa67e2c2

services/core/java/com/android/server/wm/TaskFragment.java

@@ -1825,8 +1825,6 @@ class TaskFragment extends WindowContainer<WindowContainer> {
             return false;
         }
         if (tda == null) {
-            Slog.w(TAG, "Can't find TaskDisplayArea to determine support for multi"
-                    + " window. Task id=" + getTaskId() + " attached=" + isAttached());
             return false;
         }
         if (!getTask().isResizeable() && !tda.supportsNonResizableMultiWindow()) {