Revert of [mojo] Use a pipe path to initialise Mojo in elevated utility processes.

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 36f0c5098c7207548f6ebf73ae41f2bf63daad27..6b88b049946b6e3165a108430f2bb2949814d283 100644
--- a/content/browser/child_process_launcher.cc
+++ b/content/browser/child_process_launcher.cc
@@ -25,8 +25,6 @@
 #include "content/public/common/result_codes.h"
 #include "content/public/common/sandboxed_process_launcher_delegate.h"
 #include "mojo/edk/embedder/embedder.h"
-#include "mojo/edk/embedder/named_platform_channel_pair.h"
-#include "mojo/edk/embedder/platform_channel_pair.h"
 #include "mojo/edk/embedder/scoped_platform_handle.h"
 
 #if defined(OS_WIN)
@@ -144,8 +142,9 @@
   base::Process process;
 #if defined(OS_WIN)
   if (launch_elevated) {
-    // When establishing a Mojo connection, the pipe path has already been added
-    // to the command line.
+    // TODO(rockot): We may want to support Mojo IPC to elevated processes as
+    // well, but this isn't currently feasible without sharing a pipe path on
+    // the command line as elevated process launch goes through ShellExecuteEx.
     base::LaunchOptions options;
     options.start_hidden = true;
     process = base::LaunchElevatedProcess(*cmd_line, options);
@@ -455,19 +454,8 @@
   NotifyCallback reply_callback(base::Bind(&ChildProcessLauncher::DidLaunch,
                                            weak_factory_.GetWeakPtr(),
                                            terminate_child_on_shutdown_));
-  mojo::edk::ScopedPlatformHandle client_handle;
-#if defined(OS_WIN)
-  if (delegate->ShouldLaunchElevated()) {
-    mojo::edk::NamedPlatformChannelPair named_pair;
-    mojo_host_platform_handle_ = named_pair.PassServerHandle();
-    named_pair.PrepareToPassClientHandleToChildProcess(cmd_line);
-  } else
-#endif
-  {
-    mojo::edk::PlatformChannelPair channel_pair;
-    mojo_host_platform_handle_ = channel_pair.PassServerHandle();
-    client_handle = channel_pair.PassClientHandle();
-  }
+  mojo::edk::ScopedPlatformHandle client_handle =
+      mojo_platform_channel_.PassClientHandle();
   BrowserThread::PostTask(
       BrowserThread::PROCESS_LAUNCHER, FROM_HERE,
       base::Bind(&LaunchOnLauncherThread, reply_callback, client_thread_id_,
@@ -557,7 +545,7 @@
   if (process_.IsValid()) {
     // Set up Mojo IPC to the new process.
     mojo::edk::ChildProcessLaunched(process_.Handle(),
-                                    std::move(mojo_host_platform_handle_));
+                                    mojo_platform_channel_.PassServerHandle());
   }
 
 #if defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID)