Replace the DownloadFileManager with direct ownership

content/browser/download/download_item_impl.h

Index: content/browser/download/download_item_impl.h
diff --git a/content/browser/download/download_item_impl.h b/content/browser/download/download_item_impl.h
index bbf531b789280495bdecd635863d3c07643ae5f5..4f3d2e5d06e21a1d9fae1c3114c5bff991b293b1 100644
--- a/content/browser/download/download_item_impl.h
+++ b/content/browser/download/download_item_impl.h
@@ -17,6 +17,7 @@
 #include "content/browser/download/download_net_log_parameters.h"
 #include "content/browser/download/download_request_handle.h"
 #include "content/common/content_export.h"
+#include "content/public/browser/download_destination_observer.h"
 #include "content/public/browser/download_id.h"
 #include "content/public/browser/download_item.h"
 #include "googleurl/src/gurl.h"
@@ -25,8 +26,14 @@
 
 class DownloadItemImplDelegate;
 
+namespace content {
+class DownloadFile;
+}
+
 // See download_item.h for usage.
-class CONTENT_EXPORT DownloadItemImpl : public content::DownloadItem {
+class CONTENT_EXPORT DownloadItemImpl
+    : public content::DownloadItem,
+      public content::DownloadDestinationObserver {
  public:
   // Note that it is the responsibility of the caller to ensure that a
   // DownloadItemImplDelegate passed to a DownloadItemImpl constructor
@@ -61,6 +68,9 @@ class CONTENT_EXPORT DownloadItemImpl : public content::DownloadItem {
 
   // Implementation functions (not part of the DownloadItem interface).
 
+  // Start the download
+  virtual void Start(scoped_ptr<content::DownloadFile> download_file);
+
   // Called when the target path has been determined. |target_path| is the
   // suggested target path. |disposition| indicates how the target path should
   // be used (see TargetDisposition). |danger_type| is the danger level of
@@ -81,14 +91,6 @@ class CONTENT_EXPORT DownloadItemImpl : public content::DownloadItem {
   // Set the item's DB handle.
   virtual void SetDbHandle(int64 handle);
 
-  // Cancels the off-thread aspects of the download.
-  // TODO(rdsmith): This should be private and only called from
-  // DownloadItem::Cancel/Interrupt; it isn't now because we can't
-  // call those functions from
-  // DownloadManager::FileSelectionCancelled() without doing some
-  // rewrites of the DownloadManager queues.
-  virtual void OffThreadCancel();
-
   // Called when the downloaded file is removed.
   virtual void OnDownloadedFileRemoved();
 
@@ -110,11 +112,16 @@ class CONTENT_EXPORT DownloadItemImpl : public content::DownloadItem {
   virtual void MarkAsComplete();
 
   // Called when all data has been saved. Only has display effects.
-  virtual void OnAllDataSaved(int64 size, const std::string& final_hash);
+  virtual void OnAllDataSaved(const std::string& final_hash);
 
   // Called by SavePackage to set the total number of bytes on the item.
   virtual void SetTotalBytes(int64 total_bytes);
 
+  // Provide a weak pointer reference to a DownloadDestinationObserver
+  // for use by download destinations.
+  base::WeakPtr<content::DownloadDestinationObserver>
+      DestinationObserverAsWeakPtr();
+
   // Notify observers that this item is being removed by the user.
   virtual void NotifyRemoved();
 
@@ -200,6 +207,17 @@ class CONTENT_EXPORT DownloadItemImpl : public content::DownloadItem {
   virtual void MockDownloadOpenForTesting() OVERRIDE;
 
  private:
+  // DownloadDestinationObserver
+  virtual void DestinationUpdate(int64 bytes_so_far,
+                                 int64 bytes_per_sec,
+                                 const std::string& hash_state) OVERRIDE;
+  virtual void DestinationError(
+      content::DownloadInterruptReason reason) OVERRIDE;
+  virtual void DestinationCompleted(const std::string& final_hash) OVERRIDE;
+
+  // For weak pointer downcasting.
+  friend class base::WeakPtr<content::DownloadDestinationObserver>;
+
   // Construction common to all constructors. |active| should be true for new
   // downloads and false for downloads from the history.
   // |download_type| indicates to the net log system what kind of download
@@ -215,12 +233,6 @@ class CONTENT_EXPORT DownloadItemImpl : public content::DownloadItem {
   // downloads still may block on user acceptance after this point.)
   void MaybeCompleteDownload();
 
-  // Internal helper for maintaining consistent received and total sizes, and
-  // setting the final hash.
-  // Should only be called from |OnAllDataSaved|.
-  void ProgressComplete(int64 bytes_so_far,
-                        const std::string& final_hash);
-
   // Called when the entire download operation (including renaming etc)
   // is completed.
   void Completed();
@@ -243,6 +255,10 @@ class CONTENT_EXPORT DownloadItemImpl : public content::DownloadItem {
   void OnDownloadRenamedToIntermediateName(
       content::DownloadInterruptReason reason, const FilePath& full_path);
 
+  // Callback from file thread when we initialize the DownloadFile.
+  void OnDownloadFileInitialized(
+      content::DownloadInterruptReason result);
+
   // Callback from file thread when we release the DownloadFile.
   void OnDownloadFileReleased();
 
@@ -404,6 +420,12 @@ class CONTENT_EXPORT DownloadItemImpl : public content::DownloadItem {
   // Did the delegate delay calling Complete on this download?
   bool delegate_delayed_complete_;
 
+  // DownloadFile associated with this download.  Note that this
+  // pointer may only be used or destroyed on the FILE thread.
+  // This pointer will be non-null only while the DownloadItem is in
+  // the IN_PROGRESS state.
+  scoped_ptr<content::DownloadFile> download_file_;
+
   // Net log to use for this download.
   const net::BoundNetLog bound_net_log_;