cros: Enable WebUILoginView reuse.

chrome/browser/chromeos/login/ui/webui_login_view.cc

Index: chrome/browser/chromeos/login/ui/webui_login_view.cc
diff --git a/chrome/browser/chromeos/login/ui/webui_login_view.cc b/chrome/browser/chromeos/login/ui/webui_login_view.cc
index a83d5c8f085fa1988a18c71af55731a1cad655cd..c54a61153e1bc98cceba932d216e7ffb6fb6eb98 100644
--- a/chrome/browser/chromeos/login/ui/webui_login_view.cc
+++ b/chrome/browser/chromeos/login/ui/webui_login_view.cc
@@ -21,6 +21,8 @@
 #include "chrome/browser/chromeos/accessibility/accessibility_util.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
 #include "chrome/browser/chromeos/login/ui/proxy_settings_dialog.h"
+#include "chrome/browser/chromeos/login/ui/shared_web_view.h"
+#include "chrome/browser/chromeos/login/ui/shared_web_view_factory.h"
 #include "chrome/browser/chromeos/login/ui/web_contents_set_background_color.h"
 #include "chrome/browser/chromeos/login/ui/webui_login_display.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
@@ -175,7 +177,8 @@ class WebUILoginView::StatusAreaFocusTraversable
 
 // WebUILoginView public: ------------------------------------------------------
 
-WebUILoginView::WebUILoginView() {
+WebUILoginView::WebUILoginView(const WebViewSettings& settings)
+    : settings_(settings) {
   registrar_.Add(this,
                  chrome::NOTIFICATION_LOGIN_OR_LOCK_WEBUI_VISIBLE,
                  content::NotificationService::AllSources());
@@ -249,15 +252,17 @@ WebUILoginView::~WebUILoginView() {
   } else {
     NOTIMPLEMENTED();
   }
+
+  if (is_reusing_webview_)

[xiyuan, 2016/12/09 22:37:30]

We would skip Oobe.teardown if |webui_login_| is created regardless whether it
is created from SharedWebView or from WebUILoginView ?

Should we always call Oobe.teardown if |webui_login_| is from SharedWebView
since we are going to re-use it later ?

[jdufault, 2016/12/12 18:23:09]

Good catch, thanks.

+    GetWebUI()->CallJavascriptFunctionUnsafe("cr.ui.Oobe.teardown");
 }
 
-void WebUILoginView::Init() {
-  Profile* signin_profile = ProfileHelper::GetSigninProfile();
-  webui_login_ = new views::WebView(signin_profile);
-  webui_login_->set_allow_accelerators(true);
-  AddChildView(webui_login_);
+// static
+void WebUILoginView::InitializeWebView(views::WebView* web_view) {
+  WebContents* web_contents = web_view->GetWebContents();
 
-  WebContents* web_contents = webui_login_->GetWebContents();
+  WebContentsSetBackgroundColor::CreateForWebContentsWithColor(
+      web_contents, SK_ColorTRANSPARENT);
 
   // Ensure that the login UI has a tab ID, which will allow the GAIA auth
   // extension's background script to tell it apart from a captive portal window
@@ -271,16 +276,40 @@ void WebUILoginView::Init() {
 
   // LoginHandlerViews uses a constrained window for the password manager view.
   WebContentsModalDialogManager::CreateForWebContents(web_contents);
-  WebContentsModalDialogManager::FromWebContents(web_contents)->
-      SetDelegate(this);
 
-  web_contents->SetDelegate(this);
   extensions::SetViewType(web_contents, extensions::VIEW_TYPE_COMPONENT);
   extensions::ChromeExtensionWebContentsObserver::CreateForWebContents(
       web_contents);
   content::RendererPreferences* prefs = web_contents->GetMutableRendererPrefs();
   renderer_preferences_util::UpdateFromSystemSettings(
-      prefs, signin_profile, web_contents);
+      prefs, ProfileHelper::GetSigninProfile(), web_contents);
+}
+
+void WebUILoginView::Init() {
+  Profile* signin_profile = ProfileHelper::GetSigninProfile();
+
+  if (!settings_.preloaded_url.is_empty()) {
+    SharedWebView* shared_web_view =
+        SharedWebViewFactory::GetForProfile(signin_profile);
+    webview_usage_handle_ =
+        base::MakeUnique<SharedWebViewUsageHandle>(shared_web_view);
+    is_reusing_webview_ =
+        shared_web_view->Get(settings_.preloaded_url, &webui_login_);
+  } else {
+    webui_login_ = new views::WebView(signin_profile);
+    is_reusing_webview_ = false;
+  }
+
+  WebContents* web_contents = webui_login_->GetWebContents();
+  if (!is_reusing_webview_)
+    InitializeWebView(webui_login_);
+
+  webui_login_->set_allow_accelerators(true);
+  AddChildView(webui_login_);
+
+  WebContentsModalDialogManager::FromWebContents(web_contents)
+      ->SetDelegate(this);
+  web_contents->SetDelegate(this);

[xiyuan, 2016/12/09 22:37:30]

Clear these two delegate in dtor just in case?

[jdufault, 2016/12/12 18:23:09]

Done.

 
   status_area_widget_host_ = new views::View;
   AddChildView(status_area_widget_host_);
@@ -348,12 +377,15 @@ gfx::NativeWindow WebUILoginView::GetNativeWindow() const {
   return GetWidget()->GetNativeWindow();
 }
 
-void WebUILoginView::LoadURL(const GURL & url) {
-  webui_login_->LoadInitialURL(url);
-  webui_login_->RequestFocus();
+void WebUILoginView::LoadURL(const GURL& url) {
+  // If a preloaded_url is provided then |url| must match it.
+  DCHECK(settings_.preloaded_url.is_empty() || url == settings_.preloaded_url);
 
-  WebContentsSetBackgroundColor::CreateForWebContentsWithColor(
-      GetWebContents(), SK_ColorTRANSPARENT);
+  if (is_reusing_webview_ && !settings_.preloaded_url.is_empty())
+    GetWebUI()->CallJavascriptFunctionUnsafe("cr.ui.Oobe.reload");
+  else
+    webui_login_->LoadInitialURL(url);
+  webui_login_->RequestFocus();
 
   // There is no Shell instance while running in mash.
   if (chrome::IsRunningInMash())
@@ -370,6 +402,9 @@ void WebUILoginView::LoadURL(const GURL & url) {
 }
 
 content::WebUI* WebUILoginView::GetWebUI() {
+  if (!webui_login_->web_contents())
+    return nullptr;

[xiyuan, 2016/12/09 22:37:30]

Out of curiosity, this is needed now because we reuse the webview?

[jdufault, 2016/12/12 18:23:09]

Yep.

+
   return webui_login_->web_contents()->GetWebUI();
 }
 
@@ -378,6 +413,9 @@ content::WebContents* WebUILoginView::GetWebContents() {
 }
 
 OobeUI* WebUILoginView::GetOobeUI() {
+  if (!GetWebUI())
+    return nullptr;
+
   return static_cast<OobeUI*>(GetWebUI()->GetController());
 }