[ermine] Change elevation of system panels like Ask.

Flutter changed their elevation algorithm to be relative instead
of absolute. In the last flutter roll, an elevation of 200 resulted
in wide spread shadows. Setting it to 10 relative makes is more
pleasing.

Test: Manual See: http://fxb/52630 for before and after screenshots

Bug: 52630
Change-Id: Ibb7733309963d1b0f3b7ffbb467b432e303c297b
Reviewed-on: https://fuchsia-review.googlesource.com/c/experiences/+/393794
Reviewed-by: Charles Whitten <cwhitten@google.com>
Testability-Review: Sanjay Chouksey <sanjayc@google.com>
Commit-Queue: Sanjay Chouksey <sanjayc@google.com>
diff --git a/session_shells/ermine/shell/lib/src/utils/elevations.dart b/session_shells/ermine/shell/lib/src/utils/elevations.dart
index 022e4a1..51f7f93 100644
--- a/session_shells/ermine/shell/lib/src/utils/elevations.dart
+++ b/session_shells/ermine/shell/lib/src/utils/elevations.dart
@@ -10,5 +10,5 @@
   Elevations._internal();
 
   /// Elevations for all system overlays like Ask, Status, etc.
-  static double get systemOverlayElevation => 200.0;
+  static double get systemOverlayElevation => 10.0;
 }