Revert of Moved logic for mapping child process FDs for ICU and V8 into child_process_launcher.cc

extensions/shell/browser/shell_content_browser_client.cc

Index: extensions/shell/browser/shell_content_browser_client.cc
diff --git a/extensions/shell/browser/shell_content_browser_client.cc b/extensions/shell/browser/shell_content_browser_client.cc
index c9314ad6b292e2cef7ffd9bc8e398db55b926c58..957b83087142cc75cf63e55cbbe5bb20567e3273 100644
--- a/extensions/shell/browser/shell_content_browser_client.cc
+++ b/extensions/shell/browser/shell_content_browser_client.cc
@@ -28,6 +28,7 @@
 #include "extensions/shell/browser/shell_browser_main_parts.h"
 #include "extensions/shell/browser/shell_extension_system.h"
 #include "extensions/shell/browser/shell_speech_recognition_manager_delegate.h"
+#include "gin/v8_initializer.h"
 #include "url/gurl.h"
 
 #if !defined(DISABLE_NACL)
@@ -53,7 +54,12 @@
 
 ShellContentBrowserClient::ShellContentBrowserClient(
     ShellBrowserMainDelegate* browser_main_delegate)
-    : browser_main_parts_(nullptr),
+    :
+#if defined(OS_POSIX) && !defined(OS_MACOSX)
+      v8_natives_fd_(-1),
+      v8_snapshot_fd_(-1),
+#endif  // OS_POSIX && !OS_MACOSX
+      browser_main_parts_(nullptr),
       browser_main_delegate_(browser_main_delegate) {
   DCHECK(!g_instance);
   g_instance = this;
@@ -194,6 +200,21 @@
                  site_instance->GetId()));
 }
 
+void ShellContentBrowserClient::AppendMappedFileCommandLineSwitches(
+    base::CommandLine* command_line) {
+  std::string process_type =
+      command_line->GetSwitchValueASCII(::switches::kProcessType);
+
+#if defined(OS_POSIX) && !defined(OS_MACOSX)
+#if defined(V8_USE_EXTERNAL_STARTUP_DATA)
+  DCHECK(natives_fd_exists());
+  command_line->AppendSwitch(::switches::kV8NativesPassedByFD);
+  if (snapshot_fd_exists())
+    command_line->AppendSwitch(::switches::kV8SnapshotPassedByFD);
+#endif  // V8_USE_EXTERNAL_STARTUP_DATA
+#endif  // OS_POSIX && !OS_MACOSX
+}
+
 void ShellContentBrowserClient::AppendExtraCommandLineSwitches(
     base::CommandLine* command_line,
     int child_process_id) {
@@ -233,6 +254,30 @@
   additional_allowed_schemes->push_back(kExtensionScheme);
 }
 
+#if defined(OS_POSIX) && !defined(OS_MACOSX)
+void ShellContentBrowserClient::GetAdditionalMappedFilesForChildProcess(
+    const base::CommandLine& command_line,
+    int child_process_id,
+    content::FileDescriptorInfo* mappings) {
+#if defined(V8_USE_EXTERNAL_STARTUP_DATA)
+  if (!natives_fd_exists()) {
+    int v8_natives_fd = -1;
+    int v8_snapshot_fd = -1;
+    if (gin::V8Initializer::OpenV8FilesForChildProcesses(&v8_natives_fd,
+                                                         &v8_snapshot_fd)) {
+      v8_natives_fd_.reset(v8_natives_fd);
+      v8_snapshot_fd_.reset(v8_snapshot_fd);
+    }
+  }
+  // V8 can't start up without the source of the natives, but it can
+  // start up (slower) without the snapshot.
+  DCHECK(natives_fd_exists());
+  mappings->Share(kV8NativesDataDescriptor, v8_natives_fd_.get());
+  mappings->Share(kV8SnapshotDataDescriptor, v8_snapshot_fd_.get());
+#endif  // V8_USE_EXTERNAL_STARTUP_DATA
+}
+#endif  // OS_POSIX && !OS_MACOSX
+
 content::DevToolsManagerDelegate*
 ShellContentBrowserClient::GetDevToolsManagerDelegate() {
   return new content::ShellDevToolsManagerDelegate(GetBrowserContext());