nsIDownloadManager Interface

 Creates an nsIDownload and adds it to be managed by the download manager.

 @param aSource The source URI of the transfer. Must not be null.

 @param aTarget The target URI of the transfer. Must not be null.

 @param aDisplayName The user-readable description of the transfer.
                     Can be empty.

 @param aMIMEInfo The MIME info associated with the target,
                  including MIME type and helper app when appropriate.
                  This parameter is optional.

 @param startTime Time when the download started

 @param aTempFile The location of a temporary file; i.e. a file in which
                  the received data will be stored, but which is not
                  equal to the target file. (will be moved to the real
                  target by the caller, when the download is finished)
                  May be null.

 @param aCancelable An object that can be used to abort the download.
                    Must not be null.

 @return The newly created download item with the passed-in properties.

 @note This does not actually start a download.  If you want to add and
       start a download, you need to create an nsIWebBrowserPersist, pass it
       as the aCancelable object, call this method, set the progressListener
       as the returned download object, then call saveURI.

nsIDownload addDownload(in short aDownloadType, in nsIURI aSource, in nsIURI aTarget, in AString aDisplayName, in nsIMIMEInfo aMIMEInfo, in PRTime aStartTime, in nsILocalFile aTempFile, in nsICancelable aCancelable)

 Adds a listener from the download manager.

void addListener(in nsIDownloadProgressListener aListener)

 Cancels the download with the specified ID if it's currently in-progress.
 This calls cancel(NS_BINDING_ABORTED) on the nsICancelable provided by the
 download.

 @param aID The unique ID of the download.
 @throws NS_ERROR_FAILURE if the download is not in-progress.

void cancelDownload(in unsigned long aID)

 
 Removes completed, failed, and canceled downloads from the list.

 Also notifies observers of the "download-manager-remove-download" topic
 with a null subject to allow any DM consumers to react to the removals.

void cleanUp()

 Retrieves a download managed by the download manager.  This can be one that
 is in progress, or one that has completed in the past and is stored in the
 database.

 @param aID The unique ID of the download.
 @return The download with the specified ID.
 @throws NS_ERROR_NOT_AVAILABLE if the download is not in the database.

nsIDownload getDownload(in unsigned long aID)

 Pause the specified download.

 @param aID The unique ID of the download.
 @throws NS_ERROR_FAILURE if the download is not in-progress.

void pauseDownload(in unsigned long aID)

 Removes the download with the specified id if it's not currently
 in-progress.  Whereas cancelDownload simply cancels the transfer, but
 retains information about it, removeDownload removes all knowledge of it.

 Also notifies observers of the "download-manager-remove-download" topic
 with the download id as the subject to allow any DM consumers to react to
 the removal.

 @param aID The unique ID of the download.
 @throws NS_ERROR_FAILURE if the download is active.

void removeDownload(in unsigned long aID)

 Removes all inactive downloads that were started inclusively within the
 specified time frame.

 @param aBeginTime
        The start time to remove downloads by in microseconds.
 @param aEndTime
        The end time to remove downloads by in microseconds.

void removeDownloadsByTimeframe(in long long aBeginTime, in long long aEndTime)

 Removes a listener from the download manager.

void removeListener(in nsIDownloadProgressListener aListener)

 Resume the specified download.

 @param aID The unique ID of the download.
 @throws NS_ERROR_FAILURE if the download is not in-progress.

void resumeDownload(in unsigned long aID)

 Retries a failed download.

 @param aID The unique ID of the download.
 @throws NS_ERROR_NOT_AVAILALE if the download id is not known.
 @throws NS_ERROR_FAILURE if the download is not in the following states:
           nsIDownloadManager::DOWNLOAD_CANCELED
           nsIDownloadManager::DOWNLOAD_FAILED

void retryDownload(in unsigned long aID)