chrome: respect --child-clean-exit.

content/browser/child_process_launcher.cc

Index: content/browser/child_process_launcher.cc
diff --git a/content/browser/child_process_launcher.cc b/content/browser/child_process_launcher.cc
index e497762aff8ebbd651e8467c6c0409ff7c8f8fe2..9bc7b374dfde9df24a9c9e5c2602483f13c41402 100644
--- a/content/browser/child_process_launcher.cc
+++ b/content/browser/child_process_launcher.cc
@@ -339,19 +339,23 @@ class ChildProcessLauncher::Context
     if (!process_.handle())
       return;
 
-    if (!terminate_child_on_shutdown_)
-      return;
-
-    // On Posix, EnsureProcessTerminated can lead to 2 seconds of sleep!  So
-    // don't this on the UI/IO threads.
-    BrowserThread::PostTask(
-        BrowserThread::PROCESS_LAUNCHER, FROM_HERE,
-        base::Bind(
-            &Context::TerminateInternal,
+    if (CommandLine::ForCurrentProcess()->
+        HasSwitch(switches::kWaitForChildrenBeforeExiting))
+      // When --wait-for-children-before-exiting is provided on the command
+      // line, we want the UI thread to wait for the zygote to exit before
+      // proceeding with the rest of the shut down.
+      TerminateAndWaitForExit(zygote_, process_.handle());
+    else
+      // On Posix, EnsureProcessTerminated can lead to 2 seconds of sleep!  So
+      // don't this on the UI/IO threads.
+      BrowserThread::PostTask(
+          BrowserThread::PROCESS_LAUNCHER, FROM_HERE,
+          base::Bind(
+              &Context::TerminateInternal,
 #if defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID)
-            zygote_,
+              zygote_,
 #endif
-            process_.handle()));
+              process_.handle()));
     process_.set_handle(base::kNullProcessHandle);
   }
 
@@ -361,6 +365,20 @@ class ChildProcessLauncher::Context
     process.SetProcessBackgrounded(background);
   }
 
+  static void TerminateAndWaitForExit(
+      bool zygote,
+      base::ProcessHandle handle) {
+    base::Process process(handle);
+    if (zygote) {
+      while(ZygoteHostImpl::GetInstance()->GetTerminationStatus(
+          handle,
+          false,
+          NULL) == base::TERMINATION_STATUS_STILL_RUNNING)
+        sleep(2);
+    }
+    process.Close();
+  }
+
   static void TerminateInternal(
 #if defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID)
       bool zygote,