Revert of A simple, practically zero cost fallback crash handler for Crashpad handler process.

components/crash/content/app/fallback_crash_handler_launcher_win.h

-// Copyright 2017 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 COMPONENTS_CRASH_CONTENT_APP_FALLBACK_CRASH_HANDLER_LAUNCHER_WIN_H_
-#define COMPONENTS_CRASH_CONTENT_APP_FALLBACK_CRASH_HANDLER_LAUNCHER_WIN_H_
-
-#include "base/command_line.h"
-#include "base/files/file_path.h"
-#include "base/macros.h"
-#include "base/win/scoped_handle.h"
-#include "base/win/startup_information.h"
-
-#include <windows.h>
-
-namespace crash_reporter {
-
-// This class is a last-ditch crash handler for the Crashpad handler process.
-// It prepares and stores a command line, ready for dispatching when
-// an exception occurs. Everything needed to call CreateProcess is pre-allocated
-// to minimize the odds of re-faulting due to e.g. tripping over the same issue
-// that caused the initial crash.
-// This is still very much best-effort, as doing anything at all inside a
-// process that's crashed is always going to be iffy^2.
-class FallbackCrashHandlerLauncher {
- public:
-  FallbackCrashHandlerLauncher();
-  ~FallbackCrashHandlerLauncher();
-
-  // Initializes everything that's needed in LaunchAndWaitForHandler.
-  bool Initialize(const base::CommandLine& program,
-                  const base::FilePath& crashpad_database);
-
-  // Launch the pre-computed command line for the fallback error handler.
-  // The expectation is that this function will never return, as the fallback
-  // error handler should terminate it with the exception code as the process
-  // exit code. The return value from this function is therefore academic in
-  // the normal case.
-  // However, for completeness, this function returns one of:
-  // - The error from CreateProcess if it fails to launch the fallback handler.
-  // - The error from waiting on the fallback crash handler process if it
-  //   fails to wait for that process to exit.
-  // - The exit code from the fallback crash handler process.
-  // - The error encountered in retrieving the crash handler process' exit code.
-  // Note that the return value is used in testing.
-  DWORD LaunchAndWaitForHandler(EXCEPTION_POINTERS* pointers);
-
- private:
-  // A copy of the actual exception pointers made at time of exception.
-  EXCEPTION_POINTERS exception_pointers_;
-
-  // The precomputed startup info and command line for launching the fallback
-  // handler.
-  base::win::StartupInformation startup_info_;
-  // Stores the pre-cooked command line, with an allotment of zeros at the back
-  // sufficient for writing in the thread id, just before launch.
-  std::vector<wchar_t> cmd_line_;
-
-  // An inheritable handle to our own process, the raw handle is necessary
-  // for pre-computing the startup info.
-  base::win::ScopedHandle self_process_handle_;
-
-  DISALLOW_COPY_AND_ASSIGN(FallbackCrashHandlerLauncher);
-};
-
-}  // namespace crash_reporter
-
-#endif  // COMPONENTS_CRASH_CONTENT_APP_FALLBACK_CRASH_HANDLER_LAUNCHER_WIN_H_