Disable Web Notifications in Incognito

chrome/browser/permissions/permission_context_base.cc

Index: chrome/browser/permissions/permission_context_base.cc
diff --git a/chrome/browser/permissions/permission_context_base.cc b/chrome/browser/permissions/permission_context_base.cc
index fccd23005ca9d88386be7974a8d2d6555e1cfbe1..41b38b06d516e504c25fc9d37ed881198d9e64a7 100644
--- a/chrome/browser/permissions/permission_context_base.cc
+++ b/chrome/browser/permissions/permission_context_base.cc
@@ -5,11 +5,18 @@
 #include "chrome/browser/permissions/permission_context_base.h"
 
 #include <stddef.h>
+
+#include <queue>
 #include <utility>
 
+#include "base/location.h"
 #include "base/logging.h"
 #include "base/prefs/pref_service.h"
+#include "base/rand_util.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/stringprintf.h"
+#include "base/thread_task_runner_handle.h"
+#include "base/timer/timer.h"
 #include "build/build_config.h"
 #include "chrome/browser/content_settings/host_content_settings_map_factory.h"
 #include "chrome/browser/permissions/permission_request_id.h"
@@ -17,12 +24,16 @@
 #include "chrome/browser/permissions/permission_util.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/pref_names.h"
+#include "components/content_settings/core/browser/content_settings_info.h"
+#include "components/content_settings/core/browser/content_settings_registry.h"
 #include "components/content_settings/core/browser/host_content_settings_map.h"
 #include "components/content_settings/core/browser/website_settings_registry.h"
 #include "components/variations/variations_associated_data.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/web_contents.h"
+#include "content/public/browser/web_contents_observer.h"
+#include "content/public/browser/web_contents_user_data.h"
 #include "content/public/common/origin_util.h"
 
 #if defined(OS_ANDROID)
@@ -32,6 +43,105 @@
 #include "chrome/browser/ui/website_settings/permission_bubble_manager.h"
 #endif
 
+namespace {
+
+// At most one of these is attached to each WebContents.
+class VisibilityTimerTabHelper
+    : public content::WebContentsObserver,
+      public content::WebContentsUserData<VisibilityTimerTabHelper> {
+ public:
+  ~VisibilityTimerTabHelper() override {};
+
+  // Runs |task| after the WebContents has been visible for a consecutive
+  // duration of at least |visible_delay|.
+  void PostTaskAfterVisibleDelay(const tracked_objects::Location& from_here,
+                                 const base::Closure& task,
+                                 base::TimeDelta visible_delay);
+
+  // WebContentsObserver:
+  void WasShown() override;
+  void WasHidden() override;
+  void WebContentsDestroyed() override;
+
+ private:
+  friend class content::WebContentsUserData<VisibilityTimerTabHelper>;
+  explicit VisibilityTimerTabHelper(content::WebContents* contents);
+
+  void RunTask(const base::Closure& task);
+
+  bool is_visible_;
+  std::queue<scoped_ptr<base::Timer>> task_queue_;
+
+  DISALLOW_COPY_AND_ASSIGN(VisibilityTimerTabHelper);
+};
+
+VisibilityTimerTabHelper::VisibilityTimerTabHelper(
+    content::WebContents* contents)
+    : content::WebContentsObserver(contents) {
+  if (!contents->GetMainFrame()) {
+    is_visible_ = false;
+  } else {
+    switch (contents->GetMainFrame()->GetVisibilityState()) {
+      case blink::WebPageVisibilityStateHidden:
+      case blink::WebPageVisibilityStatePrerender:
+        is_visible_ = false;
+        break;
+      case blink::WebPageVisibilityStateVisible:
+        is_visible_ = true;
+        break;
+    }
+  }
+}
+
+void VisibilityTimerTabHelper::PostTaskAfterVisibleDelay(
+    const tracked_objects::Location& from_here,
+    const base::Closure& task,
+    base::TimeDelta visible_delay) {
+  // Safe to use Unretained, as destroying this will destroy task_queue_, hence
+  // cancelling all timers.
+  task_queue_.push(make_scoped_ptr(new base::Timer(
+      from_here, visible_delay, base::Bind(&VisibilityTimerTabHelper::RunTask,
+                                           base::Unretained(this), task),
+      false /* is_repeating */)));
+  DCHECK(!task_queue_.back()->IsRunning());
+  if (is_visible_ && task_queue_.size() == 1)
+    task_queue_.front()->Reset();
+}
+
+void VisibilityTimerTabHelper::WasShown() {
+  if (!is_visible_ && !task_queue_.empty())
+    task_queue_.front()->Reset();
+  is_visible_ = true;
+}
+
+void VisibilityTimerTabHelper::WasHidden() {
+  if (is_visible_ && !task_queue_.empty())
+    task_queue_.front()->Stop();
+  is_visible_ = false;
+}
+
+void VisibilityTimerTabHelper::WebContentsDestroyed() {
+  // Delete ourselves, to avoid running tasks after WebContents is destroyed.
+  web_contents()->RemoveUserData(UserDataKey());
+  // |this| has been deleted now.
+}
+
+void VisibilityTimerTabHelper::RunTask(const base::Closure& task) {
+  DCHECK(is_visible_);
+  task.Run();
+  task_queue_.pop();
+  if (!task_queue_.empty()) {
+    task_queue_.front()->Reset();
+    return;
+  }
+  web_contents()->RemoveUserData(UserDataKey());
+  // |this| has been deleted now.
+}
+
+}  // namespace
+
+DEFINE_WEB_CONTENTS_USER_DATA_KEY(VisibilityTimerTabHelper);
+
 // static
 const char PermissionContextBase::kPermissionsKillSwitchFieldStudy[] =
     "PermissionsKillSwitch";
@@ -169,6 +279,31 @@ void PermissionContextBase::DecidePermission(
     const BrowserPermissionCallback& callback) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
 
+  // Some permissions are always denied in incognito. To prevent sites from

[mlamouri (slow - plz ping), 2016/01/11 16:03:57]

Today, that's only Push, right? Do we have plans to add more?

[johnme, 2016/01/11 16:29:20]

Push and notifications. We probably won't add any more. In fact,
PushMessagingPermissionContext overrides DecidePermission, so this particular
block of code is only used by notifications.

+  // using these to detect whether incognito mode is active, we deny after a
+  // random time delay, to simulate a user clicking a bubble/infobar.
+  if (profile()->IsOffTheRecord()) {
+    const content_settings::ContentSettingsInfo* info =
+        content_settings::ContentSettingsRegistry::GetInstance()->Get(
+            content_settings_type_);

[mlamouri (slow - plz ping), 2016/01/11 16:03:57]

Why are we getting the information from content settings? It seems that it would
be better if this information was in the permission context instead. This is
what we did for the HTTPS-only case for example. WDYT?

[johnme, 2016/01/11 16:29:20]

I could move this block of code to a
NotificationPermissionContext::DecidePermission override instead. However we
still need DENY_IN_INCOGNITO_AFTER_DELAY to be stored in ContentSettingsInfo so
that HostContentSettingsMap knows not to inherit the permission (for both push
and notifications - see https://codereview.chromium.org/1442083002), and
PermissionSelectorView knows to disable the origin info bubble dropdown (only
for notifications, since push isn't shown in OIB). And since this block of code
is the main consequence of DENY_IN_INCOGNITO_AFTER_DELAY, it seemed nice for it
to be controlled by setting DENY_IN_INCOGNITO_AFTER_DELAY in
ContentSettingsInfo, rather than having NotificationPermissionContext hardcode
that fact that notifications uses DENY_IN_INCOGNITO_AFTER_DELAY. WDYT?

[johnme, 2016/01/12 18:04:52]

Ok, I've moved all this code from PermissionContextBase to
NotificationPermissionContext.

+    if (info &&
+        info->incognito_behavior() == content_settings::ContentSettingsInfo::
+                                          DENY_IN_INCOGNITO_AFTER_DELAY) {
+      // Random number of seconds in the range [1.0, 2.0).
+      double delay_seconds = 1.0 + 1.0 * base::RandDouble();
+      VisibilityTimerTabHelper::CreateForWebContents(web_contents);
+      VisibilityTimerTabHelper::FromWebContents(web_contents)
+          ->PostTaskAfterVisibleDelay(
+              FROM_HERE,
+              base::Bind(&PermissionContextBase::NotifyPermissionSet,
+                         weak_factory_.GetWeakPtr(), id, requesting_origin,
+                         embedding_origin, callback, true /* persist */,
+                         CONTENT_SETTING_BLOCK),
+              base::TimeDelta::FromSecondsD(delay_seconds));
+      return;
+    }
+  }
+
 #if !defined(OS_ANDROID)
   PermissionBubbleManager* bubble_manager =
       PermissionBubbleManager::FromWebContents(web_contents);