Remove WebContents::WasHidden() calls in chrome::AddRestoredTab() and TabLoader

chrome/browser/sessions/tab_loader.cc

Index: chrome/browser/sessions/tab_loader.cc
diff --git a/chrome/browser/sessions/tab_loader.cc b/chrome/browser/sessions/tab_loader.cc
index 676db802f58f34533763271946b0b924b2d9d58c..bbcc670eb08c103dc039037262ea4e4f84f5edc0 100644
--- a/chrome/browser/sessions/tab_loader.cc
+++ b/chrome/browser/sessions/tab_loader.cc
@@ -174,17 +174,12 @@ void TabLoader::LoadNextTab() {
     content::WebContents* contents = controller->GetWebContents();
     if (contents) {
       Browser* browser = chrome::FindBrowserWithWebContents(contents);
-      if (browser &&
-          browser->tab_strip_model()->GetActiveWebContents() != contents) {
-        // By default tabs are marked as visible. As only the active tab is
-        // visible we need to explicitly tell non-active tabs they are hidden.
-        // Without this call non-active tabs are not marked as backgrounded.
-        //
-        // NOTE: We need to do this here rather than when the tab is added to
-        // the Browser as at that time not everything has been created, so that
-        // the call would do nothing.
-        contents->WasHidden();
-      }
+      bool is_active = browser &&
+          browser->tab_strip_model()->GetActiveWebContents() == contents;
+
+      // Background tabs should have been loaded with WebContents::CreateParams
+      // initially_hidden = true. Ensure this is reflected in the tab status.
+      DCHECK_EQ(is_active, contents->GetRenderWidgetHostView()->IsShowing());
     }
   }