Promote SetForceKeepSessionState from CookieMonster to CookieStore

Calling it on other CookieStore implementations does nothing,
but this removes the need for GetCookieMonster.

BUG=579653

Review URL: https://codereview.chromium.org/1670653002

Cr-Commit-Position: refs/heads/master@{#374019}

content/browser/browser_context.cc

@@ -22,7 +22,6 @@
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/browser/site_instance.h"
-#include "net/cookies/cookie_monster.h"
 #include "net/cookies/cookie_store.h"
 #include "net/ssl/channel_id_service.h"
 #include "net/ssl/channel_id_store.h"
@@ -78,8 +77,7 @@ void SaveSessionStateOnIOThread(
     const scoped_refptr<net::URLRequestContextGetter>& context_getter,
     AppCacheServiceImpl* appcache_service) {
   net::URLRequestContext* context = context_getter->GetURLRequestContext();
-  context->cookie_store()->GetCookieMonster()->
-      SetForceKeepSessionState();
+  context->cookie_store()->SetForceKeepSessionState();
   context->channel_id_service()->GetChannelIDStore()->
       SetForceKeepSessionState();
   appcache_service->set_force_keep_session_state();

net/cookies/cookie_monster.cc

@@ -934,6 +934,11 @@ void CookieMonster::FlushStore(const base::Closure& callback) {
     base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE, callback);
 }
 
+void CookieMonster::SetForceKeepSessionState() {
+  if (store_)
+    store_->SetForceKeepSessionState();
+}
+
 void CookieMonster::SetAllCookiesAsync(const CookieList& list,
                                        const SetCookiesCallback& callback) {
   scoped_refptr<SetAllCookiesTask> task =
@@ -1047,12 +1052,6 @@ void CookieMonster::SetKeepExpiredCookies() {
   keep_expired_cookies_ = true;
 }
 
-void CookieMonster::SetForceKeepSessionState() {
-  if (store_.get()) {
-    store_->SetForceKeepSessionState();
-  }
-}
-
 // This function must be called before the CookieMonster is used.
 void CookieMonster::SetPersistSessionCookies(bool persist_session_cookies) {
   DCHECK(!initialized_);

net/cookies/cookie_monster.h

@@ -200,6 +200,7 @@ class NET_EXPORT CookieMonster : public CookieStore {
       const DeleteCallback& callback) override;
   void DeleteSessionCookiesAsync(const DeleteCallback&) override;
   void FlushStore(const base::Closure& callback) override;
+  void SetForceKeepSessionState() override;
 
   CookieMonster* GetCookieMonster() override;
 
@@ -213,9 +214,6 @@ class NET_EXPORT CookieMonster : public CookieStore {
   // arbitrary cookies.
   void SetKeepExpiredCookies();
 
-  // Protects session cookies from deletion on shutdown.
-  void SetForceKeepSessionState();
-
   // Enables writing session cookies into the cookie database. If this this
   // method is called, it must be called before first use of the instance
   // (i.e. as part of the instance initialization process).

net/cookies/cookie_store.cc

@@ -16,4 +16,8 @@ void CookieStore::DeleteAllAsync(const DeleteCallback& callback) {
   DeleteAllCreatedBetweenAsync(base::Time(), base::Time::Max(), callback);
 }
 
+void CookieStore::SetForceKeepSessionState() {
+  // By default, do nothing.
+}
+
 }  // namespace net

net/cookies/cookie_store.h

@@ -155,6 +155,11 @@ class NET_EXPORT CookieStore : public base::RefCountedThreadSafe<CookieStore> {
   // https://crbug.com/46185
   virtual void FlushStore(const base::Closure& callback) = 0;
 
+  // Protects session cookies from deletion on shutdown, if the underlying
+  // CookieStore implemention is currently configured to store them to disk.
+  // Otherwise, does nothing.
+  virtual void SetForceKeepSessionState();
+
   // Returns the underlying CookieMonster.
   virtual CookieMonster* GetCookieMonster() = 0;