Use default shadow elevation.

components/exo/shell_surface_unittest.cc

Index: components/exo/shell_surface_unittest.cc
diff --git a/components/exo/shell_surface_unittest.cc b/components/exo/shell_surface_unittest.cc
index b8dbca007cdafa6c31cf54ddb122ca53ae5db140..4cf13ebf104eda845e5368a007bfce3ae658f556 100644
--- a/components/exo/shell_surface_unittest.cc
+++ b/components/exo/shell_surface_unittest.cc
@@ -621,7 +621,7 @@ TEST_F(ShellSurfaceTest, SurfaceShadow) {
   shell_surface->SetRectangularSurfaceShadow(gfx::Rect(10, 10, 100, 100));
   surface->Commit();
 
-  EXPECT_EQ(wm::ShadowElevation::MEDIUM, GetShadowElevation(window));
+  EXPECT_EQ(wm::ShadowElevation::DEFAULT, GetShadowElevation(window));
   EXPECT_TRUE(shadow->layer()->visible());
 
   // For surface shadow, the underlay is placed at the bottom of shell surfaces.
@@ -698,7 +698,7 @@ TEST_F(ShellSurfaceTest, NonSurfaceShadow) {
   shell_surface->SetRectangularShadowEnabled(true);
   surface->Commit();
 
-  EXPECT_EQ(wm::ShadowElevation::MEDIUM, GetShadowElevation(window));
+  EXPECT_EQ(wm::ShadowElevation::DEFAULT, GetShadowElevation(window));
   EXPECT_TRUE(shadow->layer()->visible());
 
   // For no surface shadow, both of underlay and overlay should be stacked
@@ -744,7 +744,7 @@ TEST_F(ShellSurfaceTest, ShadowWithStateChange) {
 
   shell_surface->SetRectangularSurfaceShadow(shadow_bounds);
   surface->Commit();
-  EXPECT_EQ(wm::ShadowElevation::MEDIUM, GetShadowElevation(window));
+  EXPECT_EQ(wm::ShadowElevation::DEFAULT, GetShadowElevation(window));
 
   // Shadow overlay bounds.
   EXPECT_TRUE(shadow->layer()->visible());