Add a console control handler chrome_watcher.dll.

components/browser_watcher/exit_code_watcher_win.h

Index: components/browser_watcher/exit_code_watcher_win.h
diff --git a/components/browser_watcher/exit_code_watcher_win.h b/components/browser_watcher/exit_code_watcher_win.h
index 2494916273cb396e80ef61fdc5e39af0eb0b759c..672a52742852e43c0e3401655688103e4698c47c 100644
--- a/components/browser_watcher/exit_code_watcher_win.h
+++ b/components/browser_watcher/exit_code_watcher_win.h
@@ -41,6 +41,7 @@ class ExitCodeWatcher {
   void WaitForExit();
 
   const base::Process& process() const { return process_; }
+  int exit_code() const { return exit_code_; }
 
  private:
   // Writes |exit_code| to registry, returns true on success.
@@ -49,10 +50,13 @@ class ExitCodeWatcher {
   // The registry path the exit codes are written to.
   base::string16 registry_path_;
 
-  // Handle, PID, and creation time of the watched process.
+  // Watched process and its creation time.
   base::Process process_;
   base::Time process_creation_time_;
 
+  // The exit code of the watched process. Valid after WaitForExit.
+  int exit_code_;
+
   DISALLOW_COPY_AND_ASSIGN(ExitCodeWatcher);
 };