implementation for new duplicate download UI

chrome/browser/android/download/duplicate_download_infobar_delegate.h

Index: chrome/browser/android/download/duplicate_download_infobar_delegate.h
diff --git a/chrome/browser/android/download/duplicate_download_infobar_delegate.h b/chrome/browser/android/download/duplicate_download_infobar_delegate.h
new file mode 100644
index 0000000000000000000000000000000000000000..5caa2addda0323fab96605505cfb1a7ca032ef98
--- /dev/null
+++ b/chrome/browser/android/download/duplicate_download_infobar_delegate.h
@@ -0,0 +1,40 @@
+// Copyright 2016 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_ANDROID_DOWNLOAD_DUPLICATE_DOWNLOAD_INFOBAR_DELEGATE_H_
+#define CHROME_BROWSER_ANDROID_DOWNLOAD_DUPLICATE_DOWNLOAD_INFOBAR_DELEGATE_H_
+
+#include "components/infobars/core/confirm_infobar_delegate.h"
+
+class InfoBarService;
+
+namespace chrome {
+namespace android {
+
+// An infobar that asks if user wants to continue downloading when there is
+// already a duplicate file in storage. If user chooses to proceed,
+// a new file will be created.
+// Note that this infobar does not expire if the user subsequently navigates,
+// since such navigations won't automatically cancel the underlying download.
+class DuplicateDownloadInfoBarDelegate : public ConfirmInfoBarDelegate {
+ public:
+  // Gets the file path to be downloaded.
+  virtual std::string GetFilePath() const = 0;
+
+  // Whether the download is for offline page.
+  virtual bool IsOfflinePage() const;
+
+  virtual std::string GetPageURL() const;
+
+  base::string16 GetMessageText() const override;

[gone, 2016/11/08 01:41:50]

Group together GetMessageText and ShouldExpier?  I think they both override
InfoBarDelegate functions.

[qinmin, 2016/11/08 19:19:05]

Done.

+
+  virtual bool IsOffTheRecord() const;
+
+  bool ShouldExpire(const NavigationDetails& details) const override;
+};
+
+}  // namespace android
+}  // namespace chrome
+
+#endif  // CHROME_BROWSER_ANDROID_DOWNLOAD_DUPLICATE_DOWNLOAD_INFOBAR_DELEGATE_H_