Show the Cast toolbar icon ephemerally when Cast is in use

chrome/browser/ui/toolbar/media_router_action.cc

Index: chrome/browser/ui/toolbar/media_router_action.cc
diff --git a/chrome/browser/ui/toolbar/media_router_action.cc b/chrome/browser/ui/toolbar/media_router_action.cc
index 97c60b2a4d4204916f94fb4734162b036ff85d49..b49f18f73bc356d0dfe87e7691ac3942a0351ce0 100644
--- a/chrome/browser/ui/toolbar/media_router_action.cc
+++ b/chrome/browser/ui/toolbar/media_router_action.cc
@@ -17,8 +17,13 @@
 #include "chrome/browser/ui/toolbar/component_toolbar_actions_factory.h"
 #include "chrome/browser/ui/toolbar/media_router_action_platform_delegate.h"
 #include "chrome/browser/ui/toolbar/toolbar_action_view_delegate.h"
+#include "chrome/browser/ui/toolbar/toolbar_actions_model.h"
 #include "chrome/browser/ui/webui/media_router/media_router_dialog_controller_impl.h"
+#include "chrome/common/pref_names.h"
 #include "chrome/grit/generated_resources.h"
+#include "components/prefs/pref_service.h"
+#include "components/prefs/pref_service_factory.h"
+#include "grit/theme_resources.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/gfx/color_palette.h"
 #include "ui/gfx/image/image_skia.h"
@@ -41,17 +46,19 @@ MediaRouterAction::MediaRouterAction(Browser* browser,
       media_router::MediaRoutesObserver(GetMediaRouter(browser)),
       current_icon_(gfx::VectorIconId::MEDIA_ROUTER_IDLE),
       has_local_display_route_(false),
+      has_dialog_(false),
       delegate_(nullptr),
       browser_(browser),
       toolbar_actions_bar_(toolbar_actions_bar),
       platform_delegate_(MediaRouterActionPlatformDelegate::Create(browser)),
-      contextual_menu_(browser),
+      contextual_menu_(browser, this),
       tab_strip_model_observer_(this),
+      toolbar_actions_bar_observer_(this),
       weak_ptr_factory_(this) {
   DCHECK(browser_);
   DCHECK(toolbar_actions_bar_);
   tab_strip_model_observer_.Add(browser_->tab_strip_model());
-
+  toolbar_actions_bar_observer_.Add(toolbar_actions_bar_);
   RegisterObserver();
 }
 
@@ -66,13 +73,13 @@ std::string MediaRouterAction::GetId() const {
 void MediaRouterAction::SetDelegate(ToolbarActionViewDelegate* delegate) {
   delegate_ = delegate;
 
-  // Updates the current popup state if |delegate_| is non-null and has
+  // Updates the current dialog state if |delegate_| is non-null and has
   // WebContents ready.
   // In cases such as opening a new browser window, SetDelegate() will be
-  // called before the WebContents is set. In those cases, we update the popup
+  // called before the WebContents is set. In those cases, we update the dialog
   // state when ActiveTabChanged() is called.
   if (delegate_ && delegate_->GetCurrentWebContents())
-    UpdatePopupState();
+    UpdateDialogState();
 }
 
 gfx::Image MediaRouterAction::GetIcon(content::WebContents* web_contents,
@@ -113,7 +120,6 @@ bool MediaRouterAction::HasPopup(
 
 void MediaRouterAction::HidePopup() {
   GetMediaRouterDialogController()->HideMediaRouterDialog();
-  OnPopupHidden();
 }
 
 gfx::NativeView MediaRouterAction::GetPopupNativeView() {
@@ -143,8 +149,8 @@ bool MediaRouterAction::ExecuteAction(bool by_user) {
 }
 
 void MediaRouterAction::UpdateState() {
-  if (delegate_)
-    delegate_->UpdateState();
+  DCHECK(delegate_);
+  delegate_->UpdateState();
 }
 
 bool MediaRouterAction::DisabledClickOpensMenu() const {
@@ -166,48 +172,70 @@ void MediaRouterAction::OnRoutesUpdated(
                      return route.is_local() && route.for_display();
                    }) != routes.end();
   MaybeUpdateIcon();
+  MaybeRemoveAction();
 }
 
 void MediaRouterAction::ActiveTabChanged(content::WebContents* old_contents,
                                          content::WebContents* new_contents,
                                          int index,
                                          int reason) {
-  UpdatePopupState();
+  UpdateDialogState();
+  MaybeRemoveAction();
+}
+
+void MediaRouterAction::OnToolbarActionsBarAnimationEnded() {
+  // Depress the action if the dialog is shown, release it otherwise.
+  DCHECK(delegate_);
+  if (GetMediaRouterDialogController()->IsShowingMediaRouterDialog())
+    OnDialogShown();
 }
 
-void MediaRouterAction::OnPopupHidden() {
-  if (delegate_)
+void MediaRouterAction::OnDialogHidden() {
+  if (has_dialog_) {
+    has_dialog_ = false;
+    DCHECK(delegate_);
     delegate_->OnPopupClosed();
+  }
 }
 
-void MediaRouterAction::OnPopupShown() {
-  // We depress the action regardless of whether ExecuteAction() was user
-  // initiated.
-  if (delegate_)
+void MediaRouterAction::OnDialogShown() {
+  if (!has_dialog_) {
+    has_dialog_ = true;
+    DCHECK(delegate_);
+    // We depress the action regardless of whether ExecuteAction() was user
+    // initiated.
     delegate_->OnPopupShown(true);
+  }
+}
+
+void MediaRouterAction::ToggleVisibilityPreference() {
+  browser_->profile()->GetPrefs()->SetBoolean(
+      prefs::kMediaRouterAlwaysShowActionIcon, !ShouldAlwaysShowIcon());
+  MaybeRemoveAction();
 }
 
-void MediaRouterAction::UpdatePopupState() {
+void MediaRouterAction::UpdateDialogState() {
   MediaRouterDialogControllerImpl* controller =
       GetMediaRouterDialogController();
 
   if (!controller)
     return;
 
-  // When each browser window is created, its toolbar creates a
-  // MediaRouterAction that is only destroyed when the browser window is torn
-  // down. |controller| will keep track of that instance. If |this| was created
-  // in overflow mode, it will be destroyed when the overflow menu is closed.
-  // If SetMediaRouterAction() was previously called, this is a no-op.
+  // |controller| keeps track of |this| if |this| was created with the browser
+  // window or ephemerally by activating the Cast functionality. If |this| was
+  // created in overflow mode, it will be destroyed when the overflow menu is
+  // closed. If SetMediaRouterAction() was previously called, this is a no-op.
   if (!toolbar_actions_bar_->in_overflow_mode())
     controller->SetMediaRouterAction(weak_ptr_factory_.GetWeakPtr());
 
   // Update the button in case the pressed state is out of sync with dialog
-  // visibility.
-  if (controller->IsShowingMediaRouterDialog())
-    OnPopupShown();
-  else
-    OnPopupHidden();
+  // visibility. If we just added the ephemeral icon to the toolbar and need to
+  // depress it, we do that in |OnToolbarActionsBarAnimationEnded|.
+  DCHECK(delegate_);
+  if (ShouldAlwaysShowIcon() && controller->IsShowingMediaRouterDialog())
+    OnDialogShown();
+  else if (!controller->IsShowingMediaRouterDialog())
+    OnDialogHidden();
 }
 
 MediaRouterDialogControllerImpl*
@@ -232,11 +260,25 @@ void MediaRouterAction::MaybeUpdateIcon() {
 
     // Tell the associated view to update its icon to reflect the change made
     // above.
-    if (delegate_)
-      delegate_->UpdateState();
+    UpdateState();
+  }
+}
+
+void MediaRouterAction::MaybeRemoveAction() {
+  if (!ShouldAlwaysShowIcon() &&
+      !GetMediaRouterDialogController()->IsShowingMediaRouterDialog() &&
+      !has_local_display_route_) {
+    // Warning: |this| can be deleted here.
+    ToolbarActionsModel::Get(browser_->profile())
+        ->RemoveComponentAction(GetId());
   }
 }
 
+bool MediaRouterAction::ShouldAlwaysShowIcon() {
+  PrefService* pref_service = browser_->profile()->GetPrefs();
+  return pref_service->GetBoolean(prefs::kMediaRouterAlwaysShowActionIcon);
+}
+
 gfx::VectorIconId MediaRouterAction::GetCurrentIcon() const {
   // Highest priority is to indicate whether there's an issue.
   if (issue_) {
@@ -249,3 +291,7 @@ gfx::VectorIconId MediaRouterAction::GetCurrentIcon() const {
   return has_local_display_route_ ? gfx::VectorIconId::MEDIA_ROUTER_ACTIVE
                                   : gfx::VectorIconId::MEDIA_ROUTER_IDLE;
 }
+
+base::WeakPtr<MediaRouterAction> MediaRouterAction::GetWeakPtr() {
+  return weak_ptr_factory_.GetWeakPtr();
+}