chrome: respect --child-clean-exit.

content/app/content_main_runner.cc

Index: content/app/content_main_runner.cc
diff --git a/content/app/content_main_runner.cc b/content/app/content_main_runner.cc
index 5bbdb9b35d81c001374fa3b495ae5430bc16224a..460e6ed61770a33bdb182910643c00947afcf72a 100644
--- a/content/app/content_main_runner.cc
+++ b/content/app/content_main_runner.cc
@@ -5,6 +5,8 @@
 #include "content/public/app/content_main_runner.h"
 
 #include <stdlib.h>
+#include <sys/types.h>
+#include <sys/wait.h>
 
 #include "base/allocator/allocator_extension.h"
 #include "base/at_exit.h"
@@ -786,6 +788,13 @@ class ContentMainRunnerImpl : public ContentMainRunner {
 
     exit_manager_.reset(NULL);
 
+    // Wait for children to exit if --child-clean-exit is passed.
+    if (CommandLine::ForCurrentProcess()->
+        HasSwitch(switches::kChildCleanExit)) {
+      while (wait(NULL) != -1);
+    }
+
+
     delegate_ = NULL;
     is_shutdown_ = true;
   }