Make the file chooser use PP_ArrayOutput

ppapi/cpp/dev/file_chooser_dev.h

Index: ppapi/cpp/dev/file_chooser_dev.h
diff --git a/ppapi/cpp/dev/file_chooser_dev.h b/ppapi/cpp/dev/file_chooser_dev.h
index c2abc703073e71da43b57e9ee424d4272f8a64c9..b588ac85a379ebff01d2109f764b50c6c3e64a5f 100644
--- a/ppapi/cpp/dev/file_chooser_dev.h
+++ b/ppapi/cpp/dev/file_chooser_dev.h
@@ -5,7 +5,11 @@
 #ifndef PPAPI_CPP_DEV_FILE_CHOOSER_DEV_H_
 #define PPAPI_CPP_DEV_FILE_CHOOSER_DEV_H_
 
+#include <vector>
+
 #include "ppapi/c/dev/ppb_file_chooser_dev.h"
+#include "ppapi/cpp/completion_callback.h"
+#include "ppapi/cpp/file_ref.h"
 #include "ppapi/cpp/resource.h"
 
 namespace pp {
@@ -49,23 +53,47 @@ class FileChooser_Dev : public Resource {
   FileChooser_Dev(const FileChooser_Dev& other);
 
   /// This function displays a previously created file chooser resource as a
-  /// dialog box, prompting the user to choose a file or files. The callback is
-  /// called with PP_OK on successful completion with a file (or files) selected
-  /// or PP_ERROR_USERCANCEL if the user selected no file.
+  /// dialog box, prompting the user to choose a file or files. This function
+  /// must be called in response to a user gesture, such as a mouse click or
+  /// touch event. The callback is called with PP_OK on successful completion
+  /// with a file (or files) selected, PP_ERROR_USERCANCEL if the user selected
+  /// no file, or another error code from pp_errors.h on failure.
+  ///
+  /// @param callback The completion callback that will be executed. On success,
+  /// the selected files will be passed to the given function.
+  ///
+  /// Normally you would use a CompletionCallbackFactory to allow callbacks to
+  /// be bound to your class. See completion_callback_factory.h for more
+  /// discussion on how to use this. Your callback will generally look like:
+  ///
+  /// @code
+  ///   void OnFilesSelected(int32_t result,
+  ///                        const std::vector<pp::FileRef>& files) {
+  ///     if (result == PP_OK)
+  ///       // use files...
+  ///   }
+  /// @endcode
   ///
   /// @return PP_OK_COMPLETIONPENDING if request to show the dialog was
   /// successful, another error code from pp_errors.h on failure.
-  virtual int32_t Show(const CompletionCallback& cc);
+  virtual int32_t Show(
+      const CompletionCallbackWithOutput< std::vector<FileRef> >& callback);
+
+ protected:
+  // Heap-allocated data passed to the CallbackConverter for backwards compat.
+  struct ChooseCallbackData0_5 {
+    PP_Resource file_chooser;
+    PP_ArrayOutput output;
+    PP_CompletionCallback original_callback;
+  };
 
-  /// After a successful completion callback call from Show, this method may be
-  /// used to query the chosen files.  It should be called in a loop until it
-  /// returns an is_null() FileRef.  Depending on the PP_ChooseFileMode
-  /// requested when the FileChooser was created, the file refs will either
-  /// be readable or writable.  Their file system type will be
-  /// PP_FileSystemType_External.  If the user chose no files or cancelled the
-  /// dialog, then this method will simply return an is_null() FileRef the
-  /// first time it is called.
-  virtual FileRef GetNextChosenFile() const;
+  // Provide backwards-compatability for older versions. Converts the old-style
+  // 0.5 "iterator" interface to the new-style 0.6 "array output" interface that
+  // the caller is expecting.
+  //
+  // This takes a heap-allocated ChooseCallbackData0_5 struct passed as the
+  // user data and deletes it when the call completes.
+  static void CallbackConverter(void* user_data, int32_t result);
 };
 
 }  // namespace pp