[Blob] Blob paging to disk patch.

storage/browser/blob/blob_storage_context.h

Index: storage/browser/blob/blob_storage_context.h
diff --git a/storage/browser/blob/blob_storage_context.h b/storage/browser/blob/blob_storage_context.h
index fb593e4e47ed5109cfd499823e424f575cfb1a70..3a2ffcfba77c21b95aec4a9758ae6e44f84a210d 100644
--- a/storage/browser/blob/blob_storage_context.h
+++ b/storage/browser/blob/blob_storage_context.h
@@ -5,14 +5,17 @@
 #ifndef STORAGE_BROWSER_BLOB_BLOB_STORAGE_CONTEXT_H_
 #define STORAGE_BROWSER_BLOB_BLOB_STORAGE_CONTEXT_H_
 
+#include <list>
 #include <map>
 #include <string>
 #include <vector>
 
 #include "base/callback_forward.h"
+#include "base/containers/mru_cache.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "storage/browser/blob/blob_data_handle.h"
+#include "storage/browser/blob/blob_memory_controller.h"
 #include "storage/browser/blob/blob_storage_registry.h"
 #include "storage/browser/blob/internal_blob_data.h"
 #include "storage/browser/storage_browser_export.h"
@@ -36,6 +39,7 @@ namespace storage {
 class BlobDataBuilder;
 class BlobDataItem;
 class BlobDataSnapshot;
+class BlobMemoryController;
 class ShareableBlobDataItem;
 
 // This class handles the logistics of blob Storage within the browser process,
@@ -46,6 +50,9 @@ class STORAGE_EXPORT BlobStorageContext
     : public base::SupportsWeakPtr<BlobStorageContext> {
  public:
   BlobStorageContext();
+  BlobStorageContext(bool enable_disk,
+                     const base::FilePath& blob_storage_dir,
+                     scoped_refptr<base::TaskRunner> file_runner);
   ~BlobStorageContext();
 
   scoped_ptr<BlobDataHandle> GetBlobDataFromUUID(const std::string& uuid);
@@ -74,12 +81,9 @@ class STORAGE_EXPORT BlobStorageContext
 
   const BlobStorageRegistry& registry() { return registry_; }
 
- private:
-  typedef BlobStorageRegistry::Entry BlobRegistryEntry;
-  friend class content::BlobStorageHost;
-  friend class content::BlobStorageContextTest;
+ protected:
+  friend class BlobAsyncBuilderHost;
   friend class BlobDataHandle::BlobDataHandleShared;
-  friend class ViewBlobInternalsJob;
 
   void BuildAndStoreBlob(const BlobDataBuilder& external_builder);
 
@@ -91,6 +95,15 @@ class STORAGE_EXPORT BlobStorageContext
                                  const base::Callback<void(bool)>& done);
   // ##################################
 
+ private:
+  typedef BlobStorageRegistry::Entry BlobRegistryEntry;
+
+  friend class content::BlobStorageHost;
+  friend class content::BlobStorageContextTest;
+  friend class ViewBlobInternalsJob;
+
+  void BuildAndStoreBlob(BlobDataBuilder* external_builder);
+
   // ### Methods called by BlobStorageHost ###
   void RegisterBlobUUID(const std::string& uuid);
   bool MaybeStartAsyncBlobTransfer(const std::string& uuid);
@@ -132,12 +145,17 @@ class STORAGE_EXPORT BlobStorageContext
                   uint64_t length,
                   InternalBlobData::Builder* target_blob_data);
 
+  uint64_t GetAndIncrementItemId();
+  void UpdateItemsInRecents(BlobRegistryEntry* entry);
+
   BlobStorageRegistry registry_;
+  BlobMemoryController memory_controller_;
+  uint64_t next_item_id_ = 0;
 
   // Used to keep track of how much memory is being utilized for blob data,
   // we count only the items of TYPE_DATA which are held in memory and not
   // items of TYPE_FILE.
-  size_t memory_usage_;
+  size_t memory_usage_ = 0;
 
   DISALLOW_COPY_AND_ASSIGN(BlobStorageContext);
 };