cros-md: Remove the non-MD immersive mode code paths

chrome/browser/ui/views/tabs/tab_strip_unittest.cc

Index: chrome/browser/ui/views/tabs/tab_strip_unittest.cc
diff --git a/chrome/browser/ui/views/tabs/tab_strip_unittest.cc b/chrome/browser/ui/views/tabs/tab_strip_unittest.cc
index 596423983ffcc2ccd283ab46ecb16106a75c72a8..f0b162ef5e60144213c2e8b93c8b2784c24fc131 100644
--- a/chrome/browser/ui/views/tabs/tab_strip_unittest.cc
+++ b/chrome/browser/ui/views/tabs/tab_strip_unittest.cc
@@ -282,23 +282,15 @@ TEST_F(TabStripTest, VisibilityInOverflow) {
 }
 
 TEST_F(TabStripTest, ImmersiveMode) {
-  // Immersive mode defaults to off.
-  EXPECT_FALSE(tab_strip_->IsImmersiveStyle());
-
   // Tab strip defaults to normal tab height.
   int normal_height = Tab::GetMinimumInactiveSize().height();
   EXPECT_EQ(normal_height, tab_strip_->GetPreferredSize().height());
 
-  // Tab strip can toggle immersive mode.
-  tab_strip_->SetImmersiveStyle(true);
-  EXPECT_TRUE(tab_strip_->IsImmersiveStyle());
-
-  // Now tabs have the immersive height.
-  int immersive_height = Tab::GetImmersiveHeight();
-  EXPECT_EQ(immersive_height, tab_strip_->GetPreferredSize().height());
+  // Tab strip can toggle immersive mode by setting to offscreen.
+  tab_strip_->set_offscreen(true);
 
-  // Sanity-check immersive tabs are shorter than normal tabs.
-  EXPECT_LT(immersive_height, normal_height);
+  // Now tabs have the height zero.
+  EXPECT_EQ(0, tab_strip_->GetPreferredSize().height());
 }
 
 // Creates a tab strip in stacked layout mode and verifies that as we move