[Mac] Replace the existing browser-child mach ipc with a long-lived listener ...

chrome/app/chrome_dll_main.cc

Index: chrome/app/chrome_dll_main.cc
===================================================================
--- chrome/app/chrome_dll_main.cc	(revision 59759)
+++ chrome/app/chrome_dll_main.cc	(working copy)
@@ -80,8 +80,10 @@
 #if defined(OS_MACOSX)
 #include "app/l10n_util_mac.h"
 #include "base/mac_util.h"
+#include "base/mach_ipc_mac.h"
+#include "chrome/app/breakpad_mac.h"
+#include "chrome/browser/mach_broker_mac.h"
 #include "chrome/common/chrome_paths_internal.h"
-#include "chrome/app/breakpad_mac.h"
 #include "grit/chromium_strings.h"
 #include "third_party/WebKit/WebKit/mac/WebCoreSupport/WebSystemInterface.h"
 #endif
@@ -409,6 +411,29 @@
     mac_util::SetProcessName(reinterpret_cast<CFStringRef>(app_name));
   }
 }
+
+// Completes the Mach IPC handshake by sending this process' task port to the
+// parent process.  The parent is listening on the Mach port given by
+// |GetMachPortName()|.  The task port is used by the parent to get CPU/memory
+// stats to display in the task manager.
+void SendTaskPortToParentProcess() {
+  const mach_msg_timeout_t kTimeoutMs = 100;
+  const int32_t kMessageId = 0;
+  std::string mach_port_name = MachBroker::GetMachPortName();
+
+  base::MachSendMessage child_message(kMessageId);
+  if (!child_message.AddDescriptor(mach_task_self())) {
+    LOG(ERROR) << "child AddDescriptor(mach_task_self()) failed.";
+    return;
+  }
+
+  base::MachPortSender child_sender(mach_port_name.c_str());
+  kern_return_t err = child_sender.SendMessage(child_message, kTimeoutMs);
+  if (err != KERN_SUCCESS) {
+    LOG(ERROR) << StringPrintf("child SendMessage() failed: 0x%x %s", err,
+                               mach_error_string(err));
+  }
+}
 #endif  // defined(OS_MACOSX)
 
 void InitializeStatsTable(base::ProcessId browser_pid,
@@ -588,6 +613,7 @@
     DCHECK_NE(browser_pid, 0u);
 #elif defined(OS_MACOSX)
     browser_pid = base::GetCurrentProcId();
+    SendTaskPortToParentProcess();
 #elif defined(OS_POSIX)
     // On linux, we're in the zygote here; so we need the parent process' id.
     browser_pid = base::GetParentProcessId(base::GetCurrentProcId());