Add MinidumpCrashpadInfoWriter::InitializeFromSnapshot() and its test

minidump/minidump_module_crashpad_info_writer.h

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 23 matching lines @@
 class ModuleSnapshot;
 
 //! \brief The writer for a MinidumpModuleCrashpadInfo object in a minidump
 //!     file.
 class MinidumpModuleCrashpadInfoWriter final
     : public internal::MinidumpWritable {
  public:
   MinidumpModuleCrashpadInfoWriter();
   ~MinidumpModuleCrashpadInfoWriter() override;
 
-  //! \brief Initializes the MinidumpModuleCrashpadInfo based on \a
-  //!     module_snapshot.
+  //! \brief Initializes MinidumpModuleCrashpadInfo based on \a module_snapshot.
   //!
   //! Only data in \a module_snapshot that is considered useful will be
   //! included. For simple annotations, usefulness is determined by
   //! MinidumpSimpleStringDictionaryWriter::IsUseful().
   //!
   //! \param[in] module_snapshot The module snapshot to use as source data.
   //! \param[in] module_list_index The index of the MINIDUMP_MODULE initialized
   //!     from \a module_snapshot in the minidump file’s MINIDUMP_MODULE_LIST
   //!     stream.
   //!
@@ skipping 79 matching lines @@
 
   //! \brief Adds a MinidumpModuleCrashpadInfo to the
   //!     MinidumpModuleCrashpadInfoList.
   //!
   //! This object takes ownership of \a module and becomes its parent in the
   //! overall tree of internal::MinidumpWritable objects.
   //!
   //! \note Valid in #kStateMutable.
   void AddModule(scoped_ptr<MinidumpModuleCrashpadInfoWriter> module);
 
+  //! \brief Determines whether the object is useful.
+  //!
+  //! A useful object is one that carries data that makes a meaningful
+  //! contribution to a minidump file. An object carrying children would be
+  //! considered useful.
+  //!
+  //! \return `true` if the object is useful, `false` otherwise.
+  bool IsUseful() const;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(MinidumpModuleCrashpadInfoListWriter);
 };
 
 }  // namespace crashpad
 
 #endif  // CRASHPAD_MINIDUMP_MINIDUMP_MODULE_CRASHPAD_INFO_WRITER_H_