Fixed a caching issue where icons could stay greyscale

Test: runtest -x packages/SystemUI/tests/src/com/android/systemui/statusbar/StatusBarIconViewTest.java
Change-Id: I61a86c67b14ffcd469a1126f7e285fc3b9ea629d
Fixes: 33942177
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/StatusBarIconView.java b/packages/SystemUI/src/com/android/systemui/statusbar/StatusBarIconView.java
index a2c2fd7..399b0d2 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/StatusBarIconView.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/StatusBarIconView.java
@@ -221,6 +221,8 @@
         setContentDescription(icon.contentDescription);
         if (!iconEquals) {
             if (!updateDrawable(false /* no clear */)) return false;
+            // we have to clear the grayscale tag since it may have changed
+            setTag(R.id.icon_is_grayscale, null);
         }
         if (!levelEquals) {
             setImageLevel(icon.iconLevel);