Revert "Only use SupervisedUserNavigationObserver for child accounts."

 
This reverts commit 79024af7.

Reason for revert: This revert is required because there are scenarios where the profile becomes supervised user after the navigation observer is supposed to be created. i.e. When SupervisedUserNaivgationObserver::MaybeCreateForWebContents is called the user profile is not marked as supervised hence the navigation observer is not created. This resulted in the crashes reported in the bug below.

Bug: 1061427

Original change's description:
> Only use SupervisedUserNavigationObserver for child accounts.
> 
> This CL makes sure that SupervisedUserNavigationObserver is
> created only for supervised user accounts. This saves memory
> and processing time.
> 
> Bug: 1043232
> Change-Id: I5d13ce0261d07c29384f5ba5dc83e420ed3138dd
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2008315
> Reviewed-by: Scott Violet <sky@chromium.org>
> Reviewed-by: Dan S <danan@chromium.org>
> Commit-Queue: Yilkal Abe <yilkal@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#733750}

TBR=sky@chromium.org,danan@chromium.org,yilkal@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 1043232
Change-Id: I1767afe66b32f34736af2497793d59f598cb61b0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2102764Reviewed-by: Yilkal Abe <yilkal@chromium.org>
Commit-Queue: Yilkal Abe <yilkal@chromium.org>
Cr-Commit-Position: refs/heads/master@{#750225}

chrome/browser/supervised_user/supervised_user_navigation_observer.cc

@@ -39,22 +39,6 @@ bool IsMainFrame(content::RenderFrameHost* render_frame_host) {
 
 using content::NavigationEntry;
 
-// static
-void SupervisedUserNavigationObserver::MaybeCreateForWebContents(
-    content::WebContents* web_contents) {
-  DCHECK(web_contents);
-  Profile* user_profile =
-      Profile::FromBrowserContext(web_contents->GetBrowserContext());
-  if (!user_profile->IsSupervised())
-    return;
-
-  if (!FromWebContents(web_contents)) {
-    web_contents->SetUserData(
-        UserDataKey(),
-        base::WrapUnique(new SupervisedUserNavigationObserver(web_contents)));
-  }
-}
-
 SupervisedUserNavigationObserver::~SupervisedUserNavigationObserver() {
   supervised_user_service_->RemoveObserver(this);
 }

chrome/browser/supervised_user/supervised_user_navigation_observer.h

@@ -40,10 +40,6 @@ class SupervisedUserNavigationObserver
       public SupervisedUserServiceObserver,
       public supervised_user::mojom::SupervisedUserCommands {
  public:
-  // Creates SupervisedUserNavigationObserver if the profile is a child user.
-  static void MaybeCreateForWebContents(content::WebContents* web_contents);
-  static void CreateForWebContents(content::WebContents* web_contents) = delete;
-
   ~SupervisedUserNavigationObserver() override;
 
   const std::vector<std::unique_ptr<const sessions::SerializedNavigationEntry>>&

chrome/browser/ui/tab_helpers.cc

@@ -427,7 +427,7 @@ void TabHelpers::AttachTabHelpers(WebContents* web_contents) {
 #endif
 
 #if BUILDFLAG(ENABLE_SUPERVISED_USERS)
-  SupervisedUserNavigationObserver::MaybeCreateForWebContents(web_contents);
+  SupervisedUserNavigationObserver::CreateForWebContents(web_contents);
 #endif
 
   // --- Section 4: The warning ---