Initial implementation for sharing field trial state (win)

content/public/browser/browser_child_process_host.h

Index: content/public/browser/browser_child_process_host.h
diff --git a/content/public/browser/browser_child_process_host.h b/content/public/browser/browser_child_process_host.h
index e0f2d49e881a78627b62fb6215d6f8768d944da3..e8506d83c829fec13ca1498e47adf14fb155a1d7 100644
--- a/content/public/browser/browser_child_process_host.h
+++ b/content/public/browser/browser_child_process_host.h
@@ -6,6 +6,7 @@
 #define CONTENT_PUBLIC_BROWSER_BROWSER_CHILD_PROCESS_HOST_H_
 
 #include "base/environment.h"
+#include "base/memory/shared_memory.h"
 #include "base/process/kill.h"
 #include "base/process/process_handle.h"
 #include "base/strings/string16.h"
@@ -62,11 +63,13 @@ class CONTENT_EXPORT BrowserChildProcessHost : public IPC::Sender {
   ~BrowserChildProcessHost() override {}
 
   // Derived classes call this to launch the child process asynchronously.
-  // Takes ownership of |cmd_line| and |delegate|.
-  virtual void Launch(
-      SandboxedProcessLauncherDelegate* delegate,
-      base::CommandLine* cmd_line,
-      bool terminate_on_shutdown) = 0;
+  // Takes ownership of |cmd_line| and |delegate|. Takes in |field_trial_state|
+  // to explicitly pass its handle to be inherited on Windows to the child
+  // process via the command line.
+  virtual void Launch(SandboxedProcessLauncherDelegate* delegate,
+                      base::CommandLine* cmd_line,
+                      const base::SharedMemory* field_trial_state,
+                      bool terminate_on_shutdown) = 0;
 
   virtual const ChildProcessData& GetData() const = 0;