win: Add support for CPUTimes and StartTime to snapshot

snapshot/win/process_reader_win.h

Index: snapshot/win/process_reader_win.h
diff --git a/snapshot/win/process_reader_win.h b/snapshot/win/process_reader_win.h
index b570a5e82c6b27dfce2ba3649360f38dd48b576c..8862ce093aace6735670fdadfbd3096b6eabc903 100644
--- a/snapshot/win/process_reader_win.h
+++ b/snapshot/win/process_reader_win.h
@@ -15,6 +15,7 @@
 #ifndef CRASHPAD_SNAPSHOT_WIN_PROCESS_READER_WIN_H_
 #define CRASHPAD_SNAPSHOT_WIN_PROCESS_READER_WIN_H_
 
+#include <sys/time.h>
 #include <windows.h>
 
 #include "util/misc/initialization_state_dcheck.h"
@@ -48,6 +49,26 @@ class ProcessReaderWin {
 
   bool ReadMemory(WinVMAddress at, WinVMSize num_bytes, void* into);
 
+  //! \brief Determines the target process' start time.
+  //!
+  //! \param[out] start_time The time that the process started.
+  //! 
+  //! \return `true` on success, `false` on failure, with a warning logged. On
+  //!     failure, \a start_time will be set to represent the epoch.

[Mark Mentovai, 2015/05/04 21:29:23]

It’s OK to leave start_time undefined as far as the docs go on failure, even if
the implementation does in fact zero it. (But it doesn’t have to either.) Same
in CPUTimes().

[scottmg, 2015/05/05 16:45:48]

Done.

+  bool StartTime(timeval* start_time) const;
+
+  //! \brief Determines the target process' execution time.
+  //!
+  //! \param[out] user_time The amount of time the process has executed code in
+  //!     user mode.
+  //! \param[out] system_time The amount of time the process has executed code
+  //!     in kernel mode.
+  //!
+  //! \return `true` on success, `false` on failure, with a warning logged. On
+  //!     failure, \a user_time and \a system_time will be set to represent no
+  //!     time spent executing code in user or kernel mode.
+  bool CPUTimes(timeval* user_time, timeval* system_time) const;
+
   //! \return The modules loaded in the process. The first element (at index
   //!     `0`) corresponds to the main executable.
   const std::vector<ProcessInfo::Module>& Modules();