Persist sessionStorage on disk.

content/browser/browser_context.cc

Index: content/browser/browser_context.cc
diff --git a/content/browser/browser_context.cc b/content/browser/browser_context.cc
index 522ccd108edc29658a73f380f2713a33e3b10a37..155995d97162ec3e042ad0e014f91cca5fbd45db 100644
--- a/content/browser/browser_context.cc
+++ b/content/browser/browser_context.cc
@@ -38,6 +38,8 @@ static const char* kDownloadManagerKeyName = "download_manager";
 static const char* kFileSystemContextKeyName = "content_file_system_context";
 static const char* kIndexedDBContextKeyName = "content_indexed_db_context";
 static const char* kQuotaManagerKeyName = "content_quota_manager";
+static const char* kSaveSessionStorageOnDiskKeyName =
+    "save_session_storage_on_disk";
 
 namespace content {
 
@@ -80,9 +82,12 @@ void CreateQuotaManagerAndClients(BrowserContext* context) {
   context->SetUserData(kDatabaseTrackerKeyName,
                        new UserDataAdapter<DatabaseTracker>(db_tracker));
 
+  bool session_storage_on_disk =
+      context->GetUserData(kSaveSessionStorageOnDiskKeyName) != 0;
   FilePath path = context->IsOffTheRecord() ? FilePath() : context->GetPath();
   scoped_refptr<DOMStorageContextImpl> dom_storage_context =
-      new DOMStorageContextImpl(path, context->GetSpecialStoragePolicy());
+      new DOMStorageContextImpl(path, context->GetSpecialStoragePolicy(),
+                                session_storage_on_disk);
   context->SetUserData(
       kDOMStorageContextKeyName,
       new UserDataAdapter<DOMStorageContextImpl>(dom_storage_context));
@@ -246,6 +251,19 @@ void BrowserContext::PurgeMemory(BrowserContext* browser_context) {
   GetDOMStorageContextImpl(browser_context)->PurgeMemory();
 }
 
+// static
+bool BrowserContext::SetSaveSessionStorageOnDisk(
+    BrowserContext* browser_context, bool save_session_storage_on_disk) {
+  if (browser_context->GetUserData(kQuotaManagerKeyName)) {
+    // Too late.

[michaeln, 2012/07/10 01:16:58]

Is this case ever to be expected, if not should we DCHECK here instead? Also is
there a reason to use noop UserData instance instead of a simple bool data
member for this setting?

[marja, 2012/07/10 13:40:52]

Done. DCHECK added. I wasn't sure if it's ok to add a bool data member to
BrowserContext. Added it now.

+    return false;
+  }
+  browser_context->SetUserData(
+      kSaveSessionStorageOnDiskKeyName,
+      save_session_storage_on_disk ? new base::SupportsUserData::Data() : 0);
+  return true;
+}
+
 BrowserContext::~BrowserContext() {
   // These message loop checks are just to avoid leaks in unittests.
   if (GetUserData(kDatabaseTrackerKeyName) &&