Fix warning prompting on closing a window that will cancel downloads.

chrome/browser/download/download_test_observer.h

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_DOWNLOAD_DOWNLOAD_TEST_OBSERVER_H_
+#define CHROME_BROWSER_DOWNLOAD_DOWNLOAD_TEST_OBSERVER_H_
+#pragma once
+
+#include <set>
+
+#include "base/basictypes.h"
+#include "base/memory/ref_counted.h"
+#include "content/browser/download/download_item.h"
+#include "content/browser/download/download_manager.h"
+
+// Construction of this class defines a system state, based on some number
+// of downloads being seen in a particular state + other events that
+// may occur in the download system.  That state will be recorded if it
+// occurs at any point after construction.  When that state occurs, the class
+// is considered finished.  Callers may either probe for the finished state, or
+// wait on it.
+//
+// TODO(rdsmith): Detect manager going down, remove pointer to
+// DownloadManager, transition to finished.  (For right now we
+// just use a scoped_refptr<> to keep it around, but that may cause
+// timeouts on waiting if a DownloadManager::Shutdown() occurs which
+// cancels our in-progress downloads.)
+class DownloadTestObserver : public DownloadManager::Observer,
+                             public DownloadItem::Observer {
+ public:
+  // Action an observer should take if a dangerous download is encountered.
+  enum DangerousDownloadAction {
+    ON_DANGEROUS_DOWNLOAD_ACCEPT,  // Accept the download
+    ON_DANGEROUS_DOWNLOAD_DENY,  // Deny the download
+    ON_DANGEROUS_DOWNLOAD_FAIL  // Fail if a dangerous download is seen
+  };
+
+  // Create an object that will be considered finished when |wait_count|
+  // download items have entered state |download_finished_state|.
+  // If |finish_on_select_file| is true, the object will also be
+  // considered finished if the DownloadManager raises a
+  // SelectFileDialogDisplayed() notification.
+
+  // TODO(rdsmith): Consider rewriting the interface to take a list of events
+  // to treat as completion events.
+  DownloadTestObserver(DownloadManager* download_manager,
+                       size_t wait_count,
+                       DownloadItem::DownloadState download_finished_state,
+                       bool finish_on_select_file,
+                       DangerousDownloadAction dangerous_download_action);
+
+  virtual ~DownloadTestObserver();
+
+  // State accessors.
+  bool select_file_dialog_seen() { return select_file_dialog_seen_; }

[achuithb, 2011/10/13 23:05:08]

const

[Randy Smith (Not in Mondays), 2011/10/14 00:37:41]

Done.

+
+  // Wait for whatever state was specified in the constructor.
+  void WaitForFinished();
+
+  // Return true if everything's happened that we're configured for.
+  bool IsFinished();

[achuithb, 2011/10/13 23:05:08]

const

[Randy Smith (Not in Mondays), 2011/10/14 00:37:41]

Done.

+
+  // DownloadItem::Observer
+  virtual void OnDownloadUpdated(DownloadItem* download);

[achuithb, 2011/10/13 23:05:08]

OVERRIDE here and for the other 4 virtual methods in this class

[Randy Smith (Not in Mondays), 2011/10/14 00:37:41]

Done for the other three; NumDangerousDownloadsSeen wasn't overriding anything
and is not longer a virtual.

+  virtual void OnDownloadOpened(DownloadItem* download) {}
+
+  // DownloadManager::Observer
+  virtual void ModelChanged();
+
+  virtual void SelectFileDialogDisplayed(int32 id);
+
+  virtual size_t NumDangerousDownloadsSeen() const;
+
+ private:
+  // Called when we know that a download item is in a final state.
+  // Note that this is not the same as it first transitioning in to the
+  // final state; multiple notifications may occur once the item is in
+  // that state.  So we keep our own track of transitions into final.
+  void DownloadInFinalState(DownloadItem* download);
+
+  void SignalIfFinished();
+
+  // The observed download manager.
+  scoped_refptr<DownloadManager> download_manager_;
+
+  // The set of DownloadItem's that have transitioned to their finished state
+  // since construction of this object.  When the size of this array
+  // reaches wait_count_, we're done.
+  std::set<DownloadItem*> finished_downloads_;

[achuithb, 2011/10/13 23:05:08]

You use this particular set many times; a concise typedef (like DownloadSet)
would be nice.

[Randy Smith (Not in Mondays), 2011/10/14 00:37:41]

Done.

+
+  // The set of DownloadItem's we are currently observing.  Generally there
+  // won't be any overlap with the above; once we see the final state
+  // on a DownloadItem, we'll stop observing it.
+  std::set<DownloadItem*> downloads_observed_;
+
+  // The number of downloads to wait on completing.
+  size_t wait_count_;
+
+  // The number of downloads entered in final state in initial
+  // ModelChanged().  We use |finished_downloads_| to track the incoming
+  // transitions to final state we should ignore, and to track the
+  // number of final state transitions that occurred between
+  // construction and return from wait.  But some downloads may be in our
+  // final state (and thus be entered into |finished_downloads_|) when we
+  // construct this class.  We don't want to count those in our transition
+  // to finished.
+  int finished_downloads_at_construction_;
+
+  // Whether an internal message loop has been started and must be quit upon
+  // all downloads completing.
+  bool waiting_;
+
+  // The state on which to consider the DownloadItem finished.
+  DownloadItem::DownloadState download_finished_state_;
+
+  // True if we should transition the DownloadTestObserver to finished if
+  // the select file dialog comes up.
+  bool finish_on_select_file_;
+
+  // True if we've seen the select file dialog.
+  bool select_file_dialog_seen_;
+
+  // Action to take if a dangerous download is encountered.
+  DangerousDownloadAction dangerous_download_action_;
+
+  // Holds the download ids which were dangerous.
+  std::set<int32> dangerous_downloads_seen_;
+
+  DISALLOW_COPY_AND_ASSIGN(DownloadTestObserver);
+};
+
+// The WaitForFlush() method on this class returns after:
+//      * There are no IN_PROGRESS download items remaining on the
+//        DownloadManager.
+//      * There have been two round trip messages through the file and
+//        IO threads.
+// This almost certainly means that a Download cancel has propagated through
+// the system.
+class DownloadTestFlushObserver
+    : public DownloadManager::Observer,
+      public DownloadItem::Observer,
+      public base::RefCountedThreadSafe<DownloadTestFlushObserver> {
+ public:
+  explicit DownloadTestFlushObserver(DownloadManager* download_manager);
+
+  void WaitForFlush();
+
+  // DownloadsManager observer methods.
+  virtual void ModelChanged();

[achuithb, 2011/10/13 23:05:08]

OVERRIDE here and other 2 functions in this class

[Randy Smith (Not in Mondays), 2011/10/14 00:37:41]

Done.

+
+  // DownloadItem observer methods.
+  virtual void OnDownloadUpdated(DownloadItem* download);
+  virtual void OnDownloadOpened(DownloadItem* download) {}
+
+ protected:
+  friend class base::RefCountedThreadSafe<DownloadTestFlushObserver>;
+
+  virtual ~DownloadTestFlushObserver();
+
+ private:
+  // If we're waiting for that flush point, check the number
+  // of downloads in the IN_PROGRESS state and take appropriate
+  // action.  If requested, also observes all downloads while iterating.
+  void CheckDownloadsInProgress(bool observe_downloads);
+
+  void PingFileThread(int cycle);
+
+  void PingIOThread(int cycle);
+
+  DownloadManager* download_manager_;
+  std::set<DownloadItem*> downloads_observed_;
+  bool waiting_for_zero_inprogress_;
+
+  DISALLOW_COPY_AND_ASSIGN(DownloadTestFlushObserver);
+};
+
+#endif  // CHROME_BROWSER_DOWNLOAD_DOWNLOAD_TEST_OBSERVER_H_