There should be an UNKNOWN state to handle more conditions

Driver could report error while calculating alignment conditions.

Test: make
Bug: b/144822861
Bug: b/144905377
Change-Id: Ic184b8f30c9e40c14e6edf92cc63b5b2a82be68d
Merged-In: Ic184b8f30c9e40c14e6edf92cc63b5b2a82be68d
diff --git a/packages/SystemUI/src/com/android/systemui/dock/DockManager.java b/packages/SystemUI/src/com/android/systemui/dock/DockManager.java
index 42e065a..4ee2ed3 100644
--- a/packages/SystemUI/src/com/android/systemui/dock/DockManager.java
+++ b/packages/SystemUI/src/com/android/systemui/dock/DockManager.java
@@ -35,6 +35,12 @@
     int STATE_DOCKED_HIDE = 2;
 
     /**
+     * Indicates there's no alignment info. This could happen when the device is unable to decide
+     * its alignment condition.
+     */
+    int ALIGN_STATE_UNKNOWN = -1;
+
+    /**
      * Indicates there's no alignment issue.
      */
     int ALIGN_STATE_GOOD = 0;