Remove unused KeyboardUI::Show

BUG=None
TEST=try

Review-Url: https://codereview.chromium.org/2804953005
Cr-Commit-Position: refs/heads/master@{#462786}

ash/common/keyboard/keyboard_ui.cc

@@ -26,10 +26,6 @@ class KeyboardUIImpl : public KeyboardUI, public AccessibilityObserver {
       Shell::Get()->system_tray_notifier()->RemoveAccessibilityObserver(this);
   }
 
-  // KeyboardUI:
-  void Show() override {
-    keyboard::KeyboardController::GetInstance()->ShowKeyboard(true);
-  }
   void ShowInDisplay(const int64_t display_id) override {
     keyboard::KeyboardController::GetInstance()->ShowKeyboardInDisplay(
         display_id);

ash/common/keyboard/keyboard_ui.h

@@ -23,7 +23,6 @@ class ASH_EXPORT KeyboardUI {
 
   static std::unique_ptr<KeyboardUI> Create();
 
-  virtual void Show() = 0;
   virtual void ShowInDisplay(const int64_t display_id) = 0;
   virtual void Hide() = 0;
 

ash/mus/keyboard_ui_mus.cc

@@ -29,11 +29,6 @@ void KeyboardUIMus::Hide() {
     keyboard_->Hide();
 }
 
-void KeyboardUIMus::Show() {
-  if (keyboard_)
-    keyboard_->Show();
-}
-
 void KeyboardUIMus::ShowInDisplay(const int64_t display_id) {
   // TODO(yhanada): Send display id after adding a display_id argument to
   // |Keyboard::Show()| in keyboard.mojom. See crbug.com/585253.

ash/mus/keyboard_ui_mus.h

@@ -32,7 +32,6 @@ class KeyboardUIMus : public KeyboardUI,
 
   // KeyboardUI:
   void Hide() override;
-  void Show() override;
   void ShowInDisplay(const int64_t display_id) override;
   bool IsEnabled() override;