Initial implementation for sharing field trial state (win)

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 5a655368aa8bac219446a3ea3586a4c7b6eb7666..1fe1086107685d3166b0edd9fede34a4800e5418 100644
--- a/content/browser/child_process_launcher.cc
+++ b/content/browser/child_process_launcher.cc
@@ -121,6 +121,9 @@ void LaunchOnLauncherThread(const NotifyCallback& callback,
 #if defined(OS_ANDROID)
                             base::ScopedFD ipcfd,
 #endif
+#if defined(OS_WIN)
+                            HANDLE field_trial_handle,
+#endif
                             mojo::edk::ScopedPlatformHandle client_handle,
                             base::CommandLine* cmd_line) {
   DCHECK_CURRENTLY_ON(BrowserThread::PROCESS_LAUNCHER);
@@ -152,9 +155,12 @@ void LaunchOnLauncherThread(const NotifyCallback& callback,
   } else {
     base::HandlesToInheritVector handles;
     handles.push_back(client_handle.get().handle);
+    if (field_trial_handle)
+      handles.push_back(field_trial_handle);
     cmd_line->AppendSwitchASCII(
         mojo::edk::PlatformChannelPair::kMojoPlatformChannelHandleSwitch,
         base::UintToString(base::win::HandleToUint32(handles[0])));
+
     launch_result =
         StartSandboxedProcess(delegate, cmd_line, handles, &process);
   }
@@ -391,6 +397,9 @@ void SetProcessBackgroundedOnLauncherThread(base::Process process,
 
 ChildProcessLauncher::ChildProcessLauncher(
     SandboxedProcessLauncherDelegate* delegate,
+#if defined(OS_WIN)
+    HANDLE field_trial_handle,
+#endif
     base::CommandLine* cmd_line,
     int child_process_id,
     Client* client,
@@ -414,7 +423,11 @@ ChildProcessLauncher::ChildProcessLauncher(
       weak_factory_(this) {
   DCHECK(CalledOnValidThread());
   CHECK(BrowserThread::GetCurrentThreadIdentifier(&client_thread_id_));
+#if defined(OS_WIN)
+  Launch(delegate, field_trial_handle, cmd_line, child_process_id);
+#else
   Launch(delegate, cmd_line, child_process_id);
+#endif
 }
 
 ChildProcessLauncher::~ChildProcessLauncher() {
@@ -430,6 +443,9 @@ ChildProcessLauncher::~ChildProcessLauncher() {
 
 void ChildProcessLauncher::Launch(
     SandboxedProcessLauncherDelegate* delegate,
+#if defined(OS_WIN)
+    HANDLE field_trial_handle,
+#endif
     base::CommandLine* cmd_line,
     int child_process_id) {
   DCHECK(CalledOnValidThread());
@@ -480,6 +496,9 @@ void ChildProcessLauncher::Launch(
 #if defined(OS_ANDROID)
                  base::Passed(&ipcfd),
 #endif
+#if defined(OS_WIN)
+                 field_trial_handle,
+#endif
                  base::Passed(&client_handle), cmd_line));
 }