Move some parts of ProcessReader (in snapshot) to ProcessInfo (in util)

util/posix/process_util.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,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#ifndef CRASHPAD_UTIL_POSIX_PROCESS_UTIL_POSIX_H_
-#define CRASHPAD_UTIL_POSIX_PROCESS_UTIL_POSIX_H_
-
-#include <unistd.h>
-
-#include <string>
-#include <vector>
-
-namespace crashpad {
-
-//! \brief Obtains the arguments used to launch a process.
-//!
-//! \param[in] pid The process ID of the process to examine.
-//! \param[out] argv The process’ arguments as passed to its `main()` function
-//!     as the \a argv parameter, possibly modified by the process.
-//!
-//! \return `true` on success, with \a argv populated appropriately. Otherwise,
-//!     `false`.
-//!
-//! \note This function may spuriously return `false` when used to examine a
-//!     process that it is calling `exec()`. If examining such a process, call
-//!     this function in a retry loop with a small (100ns) delay to avoid an
-//!     erroneous assumption that \a pid is not running.
-bool ProcessArgumentsForPID(pid_t pid, std::vector<std::string>* argv);
-
-}  // namespace crashpad
-
-#endif  // CRASHPAD_UTIL_POSIX_PROCESS_UTIL_POSIX_H_