Pass StatsTable shared memory via global descriptors on Posix rather than using named shared memory.

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 b5bb3f491f070688914d8f2f8146969509e341db..ac91f5a0428762647d1a8142bed93fda59d6a02e 100644
--- a/content/browser/child_process_launcher.cc
+++ b/content/browser/child_process_launcher.cc
@@ -32,12 +32,14 @@
 #include "base/android/jni_android.h"
 #include "content/browser/android/child_process_launcher_android.h"
 #elif defined(OS_POSIX)
+#include "base/memory/shared_memory.h"
 #include "base/memory/singleton.h"
 #include "content/browser/renderer_host/render_sandbox_host_linux.h"
 #include "content/browser/zygote_host/zygote_host_impl_linux.h"
 #endif
 
 #if defined(OS_POSIX)
+#include "base/metrics/stats_table.h"
 #include "base/posix/global_descriptors.h"
 #endif
 
@@ -206,7 +208,15 @@ class ChildProcessLauncher::Context
     std::vector<FileDescriptorInfo> files_to_register;
     files_to_register.push_back(
         FileDescriptorInfo(kPrimaryIPCChannel,
-                                    base::FileDescriptor(ipcfd, false)));
+                           base::FileDescriptor(ipcfd, false)));
+    base::StatsTable* stats_table = base::StatsTable::current();
+    if (stats_table &&
+        base::SharedMemory::IsHandleValid(
+            stats_table->GetSharedMemoryHandle())) {
+      files_to_register.push_back(
+          FileDescriptorInfo(kStatsTableSharedMemFd,
+                             stats_table->GetSharedMemoryHandle()));
+    }
 
     GetContentClient()->browser()->
         GetAdditionalMappedFilesForChildProcess(*cmd_line, child_process_id,
@@ -227,8 +237,15 @@ class ChildProcessLauncher::Context
     std::vector<FileDescriptorInfo> files_to_register;
     files_to_register.push_back(
         FileDescriptorInfo(kPrimaryIPCChannel,
-                                    base::FileDescriptor(ipcfd, false)));
-
+                           base::FileDescriptor(ipcfd, false)));
+    base::StatsTable* stats_table = base::StatsTable::current();

[jam, 2013/08/25 16:22:25]

we need to have one copy of this code, not two, and also same for lines 235-240
which are also duplicated. up to you whether this is done by combining the
ifdefs for android and posix and adding android ifdefs inside of that, or using
a helper function.

[rmcilroy, 2013/08/27 14:13:06]

Done (combined ifdefs).

+    if (stats_table &&
+        base::SharedMemory::IsHandleValid(
+            stats_table->GetSharedMemoryHandle())) {
+      files_to_register.push_back(
+          FileDescriptorInfo(kStatsTableSharedMemFd,
+                             stats_table->GetSharedMemoryHandle()));
+    }
 #if !defined(OS_MACOSX)
     GetContentClient()->browser()->
         GetAdditionalMappedFilesForChildProcess(*cmd_line, child_process_id,