(fix landed) Reland of name MaximizeMode to TabletMode

ash/frame/header_view.cc

Index: ash/frame/header_view.cc
diff --git a/ash/frame/header_view.cc b/ash/frame/header_view.cc
index c59c5774b4fe34a00977d05bd1801c147549afc7..d8d1065751ae5e261ad0654d90cc8fcb0639e2fa 100644
--- a/ash/frame/header_view.cc
+++ b/ash/frame/header_view.cc
@@ -146,12 +146,12 @@
   caption_button_container_->SetVisible(true);
 }
 
-void HeaderView::OnMaximizeModeStarted() {
-  caption_button_container_->UpdateSizeButtonVisibility();
-  parent()->Layout();
-}
-
-void HeaderView::OnMaximizeModeEnded() {
+void HeaderView::OnTabletModeStarted() {
+  caption_button_container_->UpdateSizeButtonVisibility();
+  parent()->Layout();
+}
+
+void HeaderView::OnTabletModeEnded() {
   caption_button_container_->UpdateSizeButtonVisibility();
   parent()->Layout();
 }