Added card elevation when card is clicked on the lockscreen

Bug: 15381356
Bug: 15181880
Change-Id: I2dd08b80d2c6b7710d2772c8880b32ab23ec42f9
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackScrollAlgorithm.java b/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackScrollAlgorithm.java
index a48cab8..472033d 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackScrollAlgorithm.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/stack/StackScrollAlgorithm.java
@@ -228,11 +228,16 @@
             View child = algorithmState.visibleChildren.get(i);
             StackScrollState.ViewState childViewState = resultState.getViewStateForView(child);
             childViewState.dimmed = dimmed;
-            childViewState.scale = !dimmed || activatedChild == child
+            boolean isActivatedChild = activatedChild == child;
+            childViewState.scale = !dimmed || isActivatedChild
                     ? 1.0f
                     : DIMMED_SCALE;
-            if (dimmed && activatedChild != null && child != activatedChild) {
-                childViewState.alpha *= ACTIVATED_INVERSE_ALPHA;
+            if (dimmed && activatedChild != null) {
+                if (!isActivatedChild) {
+                    childViewState.alpha *= ACTIVATED_INVERSE_ALPHA;
+                } else {
+                    childViewState.zTranslation += 2.0f * mZDistanceBetweenElements;
+                }
             }
         }
     }