Revert of Use a token to initialise ChannelMojo and MojoApplication everywhere.

content/common/in_process_child_thread_params.h

Index: content/common/in_process_child_thread_params.h
diff --git a/content/common/in_process_child_thread_params.h b/content/common/in_process_child_thread_params.h
index ebbf8f6f2fca7862a80b67b50f87649f5db4ba2f..f96060bd50b49106c83678f1941acc2895f2208f 100644
--- a/content/common/in_process_child_thread_params.h
+++ b/content/common/in_process_child_thread_params.h
@@ -10,6 +10,7 @@
 #include "base/memory/ref_counted.h"
 #include "base/sequenced_task_runner.h"
 #include "content/common/content_export.h"
+#include "mojo/public/cpp/system/message_pipe.h"
 
 namespace content {
 
@@ -21,7 +22,7 @@
   InProcessChildThreadParams(
       const std::string& channel_name,
       scoped_refptr<base::SequencedTaskRunner> io_runner,
-      const std::string& ipc_token = std::string(),
+      mojo::MessagePipeHandle handle = mojo::MessagePipeHandle(),
       const std::string& application_token = std::string());
   InProcessChildThreadParams(const InProcessChildThreadParams& other);
   ~InProcessChildThreadParams();
@@ -30,7 +31,7 @@
   scoped_refptr<base::SequencedTaskRunner> io_runner() const {
     return io_runner_;
   }
-  const std::string& ipc_token() const { return ipc_token_; }
+  mojo::MessagePipeHandle handle() const { return handle_; }
   const std::string& application_token() const {
     return application_token_;
   }
@@ -38,7 +39,7 @@
  private:
   std::string channel_name_;
   scoped_refptr<base::SequencedTaskRunner> io_runner_;
-  std::string ipc_token_;
+  mojo::MessagePipeHandle handle_;
   std::string application_token_;
 };