Update from https://crrev.com/308331

base/process/process.h

Index: base/process/process.h
diff --git a/base/process/process.h b/base/process/process.h
index 50ccf8d8e455338bc4b25cf3ec3c1a60d479eef1..ad8f8eec888f2e7c9297a15d0d693f36af0c871e 100644
--- a/base/process/process.h
+++ b/base/process/process.h
@@ -9,6 +9,7 @@
 #include "base/basictypes.h"
 #include "base/move.h"
 #include "base/process/process_handle.h"
+#include "base/time/time.h"
 #include "build/build_config.h"
 
 #if defined(OS_WIN)
@@ -81,6 +82,13 @@ class BASE_EXPORT Process {
   // NOTE: On POSIX |result_code| is ignored.
   void Terminate(int result_code);
 
+  // Waits for the process to exit. Returns true on success.
+  // On POSIX, if the process has been signaled then |exit_code| is set to -1.
+  bool WaitForExit(int* exit_code);
+
+  // Same as WaitForExit() but only waits for up to |timeout|.
+  bool WaitForExitWithTimeout(TimeDelta timeout, int* exit_code);
+
   // A process is backgrounded when it's priority is lower than normal.
   // Return true if this process is backgrounded, false otherwise.
   bool IsProcessBackgrounded() const;