Don't make classes derive from ChildProcessHost, and instead have them use it through composition. This cleans up the code and makes it easier to understand (as well as more closely conform to the Google C++ style guide). It also makes it possible to add an interface around ChildProcessHost in a future change.

BUG=98716
Review URL: http://codereview.chromium.org/8774040

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@112769 0039d316-1c4b-4281-b951-d872f2087c98

14 files changed, 124 insertions, 95 deletions

diff --git a/content/browser/browser_child_process_host.cc b/content/browser/browser_child_process_host.cc
index 508dade..3e56b6e 100644
--- a/content/browser/browser_child_process_host.cc
+++ b/content/browser/browser_child_process_host.cc
@@ -17,6 +17,7 @@
 #include "content/browser/profiler_message_filter.h"
 #include "content/browser/renderer_host/resource_message_filter.h"
 #include "content/browser/trace_message_filter.h"
+#include "content/common/child_process_host.h"
 #include "content/common/plugin_messages.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/child_process_data.h"
@@ -59,10 +60,11 @@ BrowserChildProcessHost::BrowserChildProcessHost(
 #endif
       disconnect_was_alive_(false) {
   data_.type = type;
-  data_.id = GenerateChildProcessUniqueId();
+  data_.id = ChildProcessHost::GenerateChildProcessUniqueId();
 
-  AddFilter(new TraceMessageFilter);
-  AddFilter(new ProfilerMessageFilter);
+  child_process_host_.reset(new ChildProcessHost(this));
+  child_process_host_->AddFilter(new TraceMessageFilter);
+  child_process_host_->AddFilter(new ProfilerMessageFilter);
 
   g_child_process_list.Get().push_back(this);
 }
@@ -96,7 +98,7 @@ void BrowserChildProcessHost::Launch(
 #elif defined(OS_POSIX)
       use_zygote,
       environ,
-      channel()->TakeClientFileDescriptor(),
+      child_process_host()->channel()->TakeClientFileDescriptor(),
 #endif
       cmd_line,
       &client_));
@@ -112,7 +114,7 @@ base::ProcessHandle BrowserChildProcessHost::GetChildProcessHandle() const {
 
 void BrowserChildProcessHost::ForceShutdown() {
   g_child_process_list.Get().remove(this);
-  ChildProcessHost::ForceShutdown();
+  child_process_host_->ForceShutdown();
 }
 
 void BrowserChildProcessHost::SetTerminateChildOnShutdown(
@@ -132,11 +134,19 @@ base::TerminationStatus BrowserChildProcessHost::GetChildTerminationStatus(
   return child_process_->GetChildTerminationStatus(exit_code);
 }
 
+bool BrowserChildProcessHost::OnMessageReceived(const IPC::Message& message) {
+  return false;
+}
+
 void BrowserChildProcessHost::OnChannelConnected(int32 peer_pid) {
   Notify(content::NOTIFICATION_CHILD_PROCESS_HOST_CONNECTED);
 }
 
-// The ChildProcessHost default implementation calls OnChildDied() always but at
+bool BrowserChildProcessHost::CanShutdown() {
+  return true;
+}
+
+// Normally a ChildProcessHostDelegate deletes itself from this callback, but at
 // this layer and below we need to have the final child process exit code to
 // properly bucket crashes vs kills. On Windows we can do this if we wait until
 // the process handle is signaled; on the rest of the platforms, we schedule a
@@ -212,7 +222,7 @@ void BrowserChildProcessHost::OnChildDisconnected() {
                             content::PROCESS_TYPE_MAX);
   // Notify in the main loop of the disconnection.
   Notify(content::NOTIFICATION_CHILD_PROCESS_HOST_DISCONNECTED);
-  OnChildDied();
+  delete this;
 }
 
 // The child process handle has been signaled so the exit code is finally
@@ -226,13 +236,17 @@ void BrowserChildProcessHost::OnWaitableEventSignaled(
   GetExitCodeProcess(waitable_event->Release(), &exit_code);
   delete waitable_event;
   if (exit_code == STILL_ACTIVE) {
-    OnChildDied();
+    delete this;
   } else {
     BrowserChildProcessHost::OnChildDisconnected();
   }
 #endif
 }
 
+bool BrowserChildProcessHost::Send(IPC::Message* message) {
+  return child_process_host_->Send(message);
+}
+
 void BrowserChildProcessHost::ShutdownStarted() {
   // Must remove the process from the list now, in case it gets used for a
   // new instance before our watcher tells us that the process terminated.
@@ -245,7 +259,7 @@ BrowserChildProcessHost::ClientHook::ClientHook(BrowserChildProcessHost* host)
 
 void BrowserChildProcessHost::ClientHook::OnProcessLaunched() {
   if (!host_->child_process_->GetHandle()) {
-    host_->OnChildDied();
+    delete host_;
     return;
   }
   host_->data_.handle = host_->child_process_->GetHandle();
diff --git a/content/browser/browser_child_process_host.h b/content/browser/browser_child_process_host.h
index a201c30..561d84e 100644
--- a/content/browser/browser_child_process_host.h
+++ b/content/browser/browser_child_process_host.h
@@ -8,13 +8,17 @@
 
 #include <list>
 
+#include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/process.h"
 #include "base/synchronization/waitable_event_watcher.h"
 #include "content/browser/child_process_launcher.h"
-#include "content/common/child_process_host.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/child_process_data.h"
+#include "content/public/common/child_process_host_delegate.h"
+#include "ipc/ipc_message.h"
+
+class ChildProcessHost;
 
 namespace base {
 class WaitableEvent;
@@ -26,9 +30,10 @@ class WaitableEvent;
 // [Browser]RenderProcessHost is the main exception that doesn't derive from
 // this class. That project lives on the UI thread.
 class CONTENT_EXPORT BrowserChildProcessHost :
-    public ChildProcessHost,
+    public content::ChildProcessHostDelegate,
     public ChildProcessLauncher::Client,
-    public base::WaitableEventWatcher::Delegate {
+    public base::WaitableEventWatcher::Delegate,
+    public IPC::Message::Sender {
  public:
   virtual ~BrowserChildProcessHost();
 
@@ -58,6 +63,9 @@ class CONTENT_EXPORT BrowserChildProcessHost :
     std::list<BrowserChildProcessHost*>::iterator iterator_;
   };
 
+  // IPC::Message::Sender override
+  virtual bool Send(IPC::Message* message) OVERRIDE;
+
   const content::ChildProcessData& data() const { return data_; }
   content::ProcessType type() const { return data_.type; }
   const string16& name() const { return data_.name; }
@@ -102,13 +110,15 @@ class CONTENT_EXPORT BrowserChildProcessHost :
   // GetExitCodeProcess()).  |exit_code| may be NULL.
   virtual base::TerminationStatus GetChildTerminationStatus(int* exit_code);
 
-  // Overrides from ChildProcessHost
-  virtual void OnChannelConnected(int32 peer_pid) OVERRIDE;
+  // ChildProcessHostDelegate implementation:
+  virtual bool CanShutdown() OVERRIDE;
   virtual void OnChildDisconnected() OVERRIDE;
   virtual void ShutdownStarted() OVERRIDE;
-  // Extends the base class implementation and removes this host from
-  // the host list. Calls ChildProcessHost::ForceShutdown
-  virtual void ForceShutdown() OVERRIDE;
+  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
+  virtual void OnChannelConnected(int32 peer_pid) OVERRIDE;
+
+  // Removes this host from the host list. Calls ChildProcessHost::ForceShutdown
+  void ForceShutdown();
 
   // Controls whether the child process should be terminated on browser
   // shutdown. Default is to always terminate.
@@ -117,6 +127,9 @@ class CONTENT_EXPORT BrowserChildProcessHost :
   // Sends the given notification on the UI thread.
   void Notify(int type);
 
+  ChildProcessHost* child_process_host() const {
+    return child_process_host_.get();
+  }
   void set_name(const string16& name) { data_.name = name; }
   void set_handle(base::ProcessHandle handle) { data_.handle = handle; }
 
@@ -133,6 +146,7 @@ class CONTENT_EXPORT BrowserChildProcessHost :
   };
 
   content::ChildProcessData data_;
+  scoped_ptr<ChildProcessHost> child_process_host_;
 
   ClientHook client_;
   scoped_ptr<ChildProcessLauncher> child_process_;
diff --git a/content/browser/gpu/gpu_process_host.cc b/content/browser/gpu/gpu_process_host.cc
index cdaac3e..3b18d38 100644
--- a/content/browser/gpu/gpu_process_host.cc
+++ b/content/browser/gpu/gpu_process_host.cc
@@ -17,6 +17,7 @@
 #include "content/browser/gpu/gpu_process_host_ui_shim.h"
 #include "content/browser/renderer_host/render_widget_host.h"
 #include "content/browser/renderer_host/render_widget_host_view.h"
+#include "content/common/child_process_host.h"
 #include "content/common/gpu/gpu_messages.h"
 #include "content/gpu/gpu_child_thread.h"
 #include "content/gpu/gpu_process.h"
@@ -279,6 +280,25 @@ GpuProcessHost::GpuProcessHost(int host_id)
 
 GpuProcessHost::~GpuProcessHost() {
   DCHECK(CalledOnValidThread());
+
+  SendOutstandingReplies();
+  UMA_HISTOGRAM_ENUMERATION("GPU.GPUProcessLifetimeEvents",
+                            DIED_FIRST_TIME + g_gpu_crash_count,
+                            GPU_PROCESS_LIFETIME_EVENT_MAX);
+
+  int exit_code;
+  base::TerminationStatus status = GetChildTerminationStatus(&exit_code);
+  UMA_HISTOGRAM_ENUMERATION("GPU.GPUProcessTerminationStatus",
+                            status,
+                            base::TERMINATION_STATUS_MAX_ENUM);
+
+  if (status == base::TERMINATION_STATUS_NORMAL_TERMINATION ||
+      status == base::TERMINATION_STATUS_ABNORMAL_TERMINATION) {
+    UMA_HISTOGRAM_ENUMERATION("GPU.GPUProcessExitCode",
+                              exit_code,
+                              content::RESULT_CODE_LAST_CODE);
+  }
+
 #if defined(OS_WIN)
   if (gpu_process_)
     CloseHandle(gpu_process_);
@@ -299,14 +319,15 @@ GpuProcessHost::~GpuProcessHost() {
 }
 
 bool GpuProcessHost::Init() {
-  if (!CreateChannel())
+  if (!child_process_host()->CreateChannel())
     return false;
 
   if (in_process_) {
     CommandLine::ForCurrentProcess()->AppendSwitch(
         switches::kDisableGpuWatchdog);
 
-    in_process_gpu_thread_.reset(new GpuMainThread(channel_id()));
+    in_process_gpu_thread_.reset(new GpuMainThread(
+        child_process_host()->channel_id()));
 
     base::Thread::Options options;
 #if defined(OS_WIN)
@@ -337,7 +358,7 @@ void GpuProcessHost::RouteOnUIThread(const IPC::Message& message) {
 
 bool GpuProcessHost::Send(IPC::Message* msg) {
   DCHECK(CalledOnValidThread());
-  if (opening_channel()) {
+  if (child_process_host()->opening_channel()) {
     queued_messages_.push(msg);
     return true;
   }
@@ -488,10 +509,6 @@ void GpuProcessHost::OnGraphicsInfoCollected(const content::GPUInfo& gpu_info) {
   GpuDataManager::GetInstance()->UpdateGpuInfo(gpu_info);
 }
 
-bool GpuProcessHost::CanShutdown() {
-  return true;
-}
-
 void GpuProcessHost::OnProcessLaunched() {
   // Send the GPU process handle to the UI thread before it has to
   // respond to any requests to establish a GPU channel. The response
@@ -513,30 +530,6 @@ void GpuProcessHost::OnProcessLaunched() {
 #endif
 }
 
-void GpuProcessHost::OnChildDied() {
-  SendOutstandingReplies();
-  // Located in OnChildDied because OnProcessCrashed suffers from a race
-  // condition on Linux.
-  UMA_HISTOGRAM_ENUMERATION("GPU.GPUProcessLifetimeEvents",
-                            DIED_FIRST_TIME + g_gpu_crash_count,
-                            GPU_PROCESS_LIFETIME_EVENT_MAX);
-
-  int exit_code;
-  base::TerminationStatus status = GetChildTerminationStatus(&exit_code);
-  UMA_HISTOGRAM_ENUMERATION("GPU.GPUProcessTerminationStatus",
-                            status,
-                            base::TERMINATION_STATUS_MAX_ENUM);
-
-  if (status == base::TERMINATION_STATUS_NORMAL_TERMINATION ||
-      status == base::TERMINATION_STATUS_ABNORMAL_TERMINATION) {
-    UMA_HISTOGRAM_ENUMERATION("GPU.GPUProcessExitCode",
-                              exit_code,
-                              content::RESULT_CODE_LAST_CODE);
-  }
-
-  ChildProcessHost::OnChildDied();
-}
-
 void GpuProcessHost::OnProcessCrashed(int exit_code) {
   SendOutstandingReplies();
   if (++g_gpu_crash_count >= kGpuMaxCrashCount) {
@@ -575,7 +568,8 @@ bool GpuProcessHost::LaunchGpuProcess() {
 
   CommandLine* cmd_line = new CommandLine(exe_path);
   cmd_line->AppendSwitchASCII(switches::kProcessType, switches::kGpuProcess);
-  cmd_line->AppendSwitchASCII(switches::kProcessChannelID, channel_id());
+  cmd_line->AppendSwitchASCII(switches::kProcessChannelID,
+                              child_process_host()->channel_id());
 
   // Propagate relevant command line switches.
   static const char* const kSwitchNames[] = {
diff --git a/content/browser/gpu/gpu_process_host.h b/content/browser/gpu/gpu_process_host.h
index e6ba2c0..073e8fd 100644
--- a/content/browser/gpu/gpu_process_host.h
+++ b/content/browser/gpu/gpu_process_host.h
@@ -92,9 +92,7 @@ class GpuProcessHost : public BrowserChildProcessHost,
   // Post an IPC message to the UI shim's message handler on the UI thread.
   void RouteOnUIThread(const IPC::Message& message);
 
-  virtual bool CanShutdown() OVERRIDE;
   virtual void OnProcessLaunched() OVERRIDE;
-  virtual void OnChildDied() OVERRIDE;
   virtual void OnProcessCrashed(int exit_code) OVERRIDE;
 
   // Message handlers.
diff --git a/content/browser/plugin_data_remover_impl.cc b/content/browser/plugin_data_remover_impl.cc
index da0dbfc..38489d5 100644
--- a/content/browser/plugin_data_remover_impl.cc
+++ b/content/browser/plugin_data_remover_impl.cc
@@ -10,6 +10,7 @@
 #include "base/version.h"
 #include "content/browser/plugin_process_host.h"
 #include "content/browser/plugin_service.h"
+#include "content/common/child_process_host.h"
 #include "content/common/plugin_messages.h"
 #include "content/public/browser/browser_thread.h"
 #include "webkit/plugins/npapi/plugin_group.h"
diff --git a/content/browser/plugin_loader_posix.cc b/content/browser/plugin_loader_posix.cc
index 6d2be85..bc96427 100644
--- a/content/browser/plugin_loader_posix.cc
+++ b/content/browser/plugin_loader_posix.cc
@@ -8,6 +8,7 @@
 #include "base/message_loop.h"
 #include "base/message_loop_proxy.h"
 #include "base/metrics/histogram.h"
+#include "content/common/child_process_host.h"
 #include "content/common/utility_messages.h"
 #include "content/public/browser/browser_thread.h"
 #include "webkit/plugins/npapi/plugin_list.h"
diff --git a/content/browser/plugin_process_host.cc b/content/browser/plugin_process_host.cc
index 91c22c4..293072d 100644
--- a/content/browser/plugin_process_host.cc
+++ b/content/browser/plugin_process_host.cc
@@ -22,6 +22,7 @@
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "content/browser/plugin_service.h"
+#include "content/common/child_process_host.h"
 #include "content/common/plugin_messages.h"
 #include "content/common/resource_messages.h"
 #include "content/public/browser/browser_thread.h"
@@ -167,7 +168,7 @@ bool PluginProcessHost::Init(const webkit::WebPluginInfo& info,
   info_ = info;
   set_name(info_.name);
 
-  if (!CreateChannel())
+  if (!child_process_host()->CreateChannel())
     return false;
 
   // Build command line for plugin. When we have a plugin launcher, we can't
@@ -180,14 +181,15 @@ bool PluginProcessHost::Init(const webkit::WebPluginInfo& info,
   // Run the plug-in process in a mode tolerant of heap execution without
   // explicit mprotect calls. Some plug-ins still rely on this quaint and
   // archaic "feature." See http://crbug.com/93551.
-  int flags = CHILD_ALLOW_HEAP_EXECUTION;
+  int flags = ChildProcessHost::CHILD_ALLOW_HEAP_EXECUTION;
 #elif defined(OS_LINUX)
-  int flags = plugin_launcher.empty() ? CHILD_ALLOW_SELF : CHILD_NORMAL;
+  int flags = plugin_launcher.empty() ? ChildProcessHost::CHILD_ALLOW_SELF :
+                                        ChildProcessHost::CHILD_NORMAL;
 #else
-  int flags = CHILD_NORMAL;
+  int flags = ChildProcessHost::CHILD_NORMAL;
 #endif
 
-  FilePath exe_path = GetChildPath(flags);
+  FilePath exe_path = ChildProcessHost::GetChildPath(flags);
   if (exe_path.empty())
     return false;
 
@@ -233,7 +235,8 @@ bool PluginProcessHost::Init(const webkit::WebPluginInfo& info,
     cmd_line->AppendSwitchASCII(switches::kLang, locale);
   }
 
-  cmd_line->AppendSwitchASCII(switches::kProcessChannelID, channel_id());
+  cmd_line->AppendSwitchASCII(switches::kProcessChannelID,
+                              child_process_host()->channel_id());
 
 #if defined(OS_POSIX)
   base::environment_vector env;
@@ -279,6 +282,10 @@ void PluginProcessHost::ForceShutdown() {
   BrowserChildProcessHost::ForceShutdown();
 }
 
+void PluginProcessHost::AddFilter(IPC::ChannelProxy::MessageFilter* filter) {
+  child_process_host()->AddFilter(filter);
+}
+
 bool PluginProcessHost::OnMessageReceived(const IPC::Message& msg) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(PluginProcessHost, msg)
@@ -359,7 +366,7 @@ void PluginProcessHost::CancelPendingRequestsForResourceContext(
 void PluginProcessHost::OpenChannelToPlugin(Client* client) {
   Notify(content::NOTIFICATION_CHILD_INSTANCE_CREATED);
   client->SetPluginInfo(info_);
-  if (opening_channel()) {
+  if (child_process_host()->opening_channel()) {
     // The channel is already in the process of being opened.  Put
     // this "open channel" request into a queue of requests that will
     // be run once the channel is open.
diff --git a/content/browser/plugin_process_host.h b/content/browser/plugin_process_host.h
index b56183f..6ce5f08 100644
--- a/content/browser/plugin_process_host.h
+++ b/content/browser/plugin_process_host.h
@@ -17,6 +17,7 @@
 #include "base/memory/ref_counted.h"
 #include "content/browser/browser_child_process_host.h"
 #include "content/common/content_export.h"
+#include "ipc/ipc_channel_proxy.h"
 #include "webkit/plugins/webplugininfo.h"
 #include "ui/gfx/native_widget_types.h"
 
@@ -69,7 +70,7 @@ class CONTENT_EXPORT PluginProcessHost : public BrowserChildProcessHost {
   bool Init(const webkit::WebPluginInfo& info, const std::string& locale);
 
   // Force the plugin process to shutdown (cleanly).
-  virtual void ForceShutdown() OVERRIDE;
+  void ForceShutdown();
 
   virtual bool OnMessageReceived(const IPC::Message& msg) OVERRIDE;
   virtual void OnChannelConnected(int32 peer_pid) OVERRIDE;
@@ -109,6 +110,9 @@ class CONTENT_EXPORT PluginProcessHost : public BrowserChildProcessHost {
   void AddWindow(HWND window);
 #endif
 
+  // Adds an IPC message filter.  A reference will be kept to the filter.
+  void AddFilter(IPC::ChannelProxy::MessageFilter* filter);
+
  private:
   // Sends a message to the plugin process to request creation of a new channel
   // for the given mime type.
diff --git a/content/browser/ppapi_plugin_process_host.cc b/content/browser/ppapi_plugin_process_host.cc
index 8b5faef..f4ccd33 100644
--- a/content/browser/ppapi_plugin_process_host.cc
+++ b/content/browser/ppapi_plugin_process_host.cc
@@ -11,6 +11,7 @@
 #include "base/utf_string_conversions.h"
 #include "content/browser/plugin_service.h"
 #include "content/browser/renderer_host/render_message_filter.h"
+#include "content/common/child_process_host.h"
 #include "content/common/child_process_messages.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/pepper_plugin_info.h"
@@ -84,7 +85,7 @@ PpapiPluginProcessHost* PpapiPluginProcessHost::CreateBrokerHost(
 }
 
 void PpapiPluginProcessHost::OpenChannelToPlugin(Client* client) {
-  if (opening_channel()) {
+  if (child_process_host()->opening_channel()) {
     // The channel is already in the process of being opened.  Put
     // this "open channel" request into a queue of requests that will
     // be run once the channel is open.
@@ -102,7 +103,7 @@ PpapiPluginProcessHost::PpapiPluginProcessHost(net::HostResolver* host_resolver)
       network_observer_(new PluginNetworkObserver(this)),
       is_broker_(false),
       process_id_(ChildProcessHost::GenerateChildProcessUniqueId()) {
-  AddFilter(filter_.get());
+  child_process_host()->AddFilter(filter_.get());
 }
 
 PpapiPluginProcessHost::PpapiPluginProcessHost()
@@ -119,7 +120,7 @@ bool PpapiPluginProcessHost::Init(const content::PepperPluginInfo& info) {
     set_name(UTF8ToUTF16(info.name));
   }
 
-  if (!CreateChannel())
+  if (!child_process_host()->CreateChannel())
     return false;
 
   const CommandLine& browser_command_line = *CommandLine::ForCurrentProcess();
@@ -140,7 +141,8 @@ bool PpapiPluginProcessHost::Init(const content::PepperPluginInfo& info) {
   cmd_line->AppendSwitchASCII(switches::kProcessType,
                               is_broker_ ? switches::kPpapiBrokerProcess
                                          : switches::kPpapiPluginProcess);
-  cmd_line->AppendSwitchASCII(switches::kProcessChannelID, channel_id());
+  cmd_line->AppendSwitchASCII(switches::kProcessChannelID,
+                              child_process_host()->channel_id());
 
   // These switches are forwarded to both plugin and broker pocesses.
   static const char* kCommonForwardSwitches[] = {
@@ -198,10 +200,6 @@ void PpapiPluginProcessHost::RequestPluginChannel(Client* client) {
     client->OnChannelOpened(base::kNullProcessHandle, IPC::ChannelHandle());
 }
 
-bool PpapiPluginProcessHost::CanShutdown() {
-  return true;
-}
-
 void PpapiPluginProcessHost::OnProcessLaunched() {
 }
 
diff --git a/content/browser/ppapi_plugin_process_host.h b/content/browser/ppapi_plugin_process_host.h
index a968a27..f92aa1d 100644
--- a/content/browser/ppapi_plugin_process_host.h
+++ b/content/browser/ppapi_plugin_process_host.h
@@ -82,7 +82,6 @@ class PpapiPluginProcessHost
 
   void RequestPluginChannel(Client* client);
 
-  virtual bool CanShutdown() OVERRIDE;
   virtual void OnProcessLaunched() OVERRIDE;
 
   virtual bool OnMessageReceived(const IPC::Message& msg) OVERRIDE;
diff --git a/content/browser/renderer_host/render_message_filter.cc b/content/browser/renderer_host/render_message_filter.cc
index 267d1cc..f84b968 100644
--- a/content/browser/renderer_host/render_message_filter.cc
+++ b/content/browser/renderer_host/render_message_filter.cc
@@ -686,8 +686,7 @@ void RenderMessageFilter::OnCheckNotificationPermission(
 void RenderMessageFilter::OnAllocateSharedMemory(
     uint32 buffer_size,
     base::SharedMemoryHandle* handle) {
-  ChildProcessHost::OnAllocateSharedMemory(
-      buffer_size, peer_handle(), handle);
+  ChildProcessHost::AllocateSharedMemory(buffer_size, peer_handle(), handle);
 }
 
 net::URLRequestContext* RenderMessageFilter::GetRequestContextForURL(
diff --git a/content/browser/utility_process_host.cc b/content/browser/utility_process_host.cc
index 65a7e70..8bc2234 100644
--- a/content/browser/utility_process_host.cc
+++ b/content/browser/utility_process_host.cc
@@ -9,6 +9,7 @@
 #include "base/command_line.h"
 #include "base/message_loop.h"
 #include "base/utf_string_conversions.h"
+#include "content/common/child_process_host.h"
 #include "content/common/utility_messages.h"
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/common/content_switches.h"
@@ -40,9 +41,9 @@ UtilityProcessHost::UtilityProcessHost(Client* client,
       is_batch_mode_(false),
       no_sandbox_(false),
 #if defined(OS_LINUX)
-      child_flags_(CHILD_ALLOW_SELF),
+      child_flags_(ChildProcessHost::CHILD_ALLOW_SELF),
 #else
-      child_flags_(CHILD_NORMAL),
+      child_flags_(ChildProcessHost::CHILD_NORMAL),
 #endif
       started_(false) {
 }
@@ -72,7 +73,7 @@ void UtilityProcessHost::EndBatchMode()  {
 }
 
 FilePath UtilityProcessHost::GetUtilityProcessCmd() {
-  return GetChildPath(child_flags_);
+  return ChildProcessHost::GetChildPath(child_flags_);
 }
 
 bool UtilityProcessHost::StartProcess() {
@@ -86,7 +87,7 @@ bool UtilityProcessHost::StartProcess() {
   // launches a UtilityProcessHost.
   set_name(ASCIIToUTF16("utility process"));
 
-  if (!CreateChannel())
+  if (!child_process_host()->CreateChannel())
     return false;
 
   FilePath exe_path = GetUtilityProcessCmd();
@@ -98,7 +99,8 @@ bool UtilityProcessHost::StartProcess() {
   CommandLine* cmd_line = new CommandLine(exe_path);
   cmd_line->AppendSwitchASCII(switches::kProcessType,
                               switches::kUtilityProcess);
-  cmd_line->AppendSwitchASCII(switches::kProcessChannelID, channel_id());
+  cmd_line->AppendSwitchASCII(switches::kProcessChannelID,
+                              child_process_host()->channel_id());
   std::string locale =
       content::GetContentClient()->browser()->GetApplicationLocale();
   cmd_line->AppendSwitchASCII(switches::kLang, locale);
@@ -151,7 +153,3 @@ void UtilityProcessHost::OnProcessCrashed(int exit_code) {
       client_thread_id_, FROM_HERE,
       base::Bind(&Client::OnProcessCrashed, client_.get(), exit_code));
 }
-
-bool UtilityProcessHost::CanShutdown() {
-  return true;
-}
diff --git a/content/browser/utility_process_host.h b/content/browser/utility_process_host.h
index de53610..b81d12d 100644
--- a/content/browser/utility_process_host.h
+++ b/content/browser/utility_process_host.h
@@ -84,7 +84,6 @@ class CONTENT_EXPORT UtilityProcessHost : public BrowserChildProcessHost {
 
   // BrowserChildProcessHost:
   virtual void OnProcessCrashed(int exit_code) OVERRIDE;
-  virtual bool CanShutdown() OVERRIDE;
 
   // A pointer to our client interface, who will be informed of progress.
   scoped_refptr<Client> client_;
diff --git a/content/browser/worker_host/worker_process_host.cc b/content/browser/worker_host/worker_process_host.cc
index ba29447..68d75c9 100644
--- a/content/browser/worker_host/worker_process_host.cc
+++ b/content/browser/worker_host/worker_process_host.cc
@@ -31,6 +31,7 @@
 #include "content/browser/worker_host/message_port_service.h"
 #include "content/browser/worker_host/worker_message_filter.h"
 #include "content/browser/worker_host/worker_service.h"
+#include "content/common/child_process_host.h"
 #include "content/common/debug_flags.h"
 #include "content/common/view_messages.h"
 #include "content/common/worker_messages.h"
@@ -111,22 +112,23 @@ WorkerProcessHost::~WorkerProcessHost() {
 }
 
 bool WorkerProcessHost::Init(int render_process_id) {
-  if (!CreateChannel())
+  if (!child_process_host()->CreateChannel())
     return false;
 
 #if defined(OS_LINUX)
-  int flags = CHILD_ALLOW_SELF;
+  int flags = ChildProcessHost::CHILD_ALLOW_SELF;
 #else
-  int flags = CHILD_NORMAL;
+  int flags = ChildProcessHost::CHILD_NORMAL;
 #endif
 
-  FilePath exe_path = GetChildPath(flags);
+  FilePath exe_path = ChildProcessHost::GetChildPath(flags);
   if (exe_path.empty())
     return false;
 
   CommandLine* cmd_line = new CommandLine(exe_path);
   cmd_line->AppendSwitchASCII(switches::kProcessType, switches::kWorkerProcess);
-  cmd_line->AppendSwitchASCII(switches::kProcessChannelID, channel_id());
+  cmd_line->AppendSwitchASCII(switches::kProcessChannelID,
+                              child_process_host()->channel_id());
   std::string locale =
       content::GetContentClient()->browser()->GetApplicationLocale();
   cmd_line->AppendSwitchASCII(switches::kLang, locale);
@@ -237,29 +239,30 @@ void WorkerProcessHost::CreateMessageFilters(int render_process_id) {
       id(), content::PROCESS_TYPE_WORKER, resource_context_,
       new URLRequestContextSelector(request_context),
       resource_dispatcher_host_);
-  AddFilter(resource_message_filter);
+  child_process_host()->AddFilter(resource_message_filter);
 
   worker_message_filter_ = new WorkerMessageFilter(
       render_process_id, resource_context_, resource_dispatcher_host_,
       base::Bind(&WorkerService::next_worker_route_id,
                  base::Unretained(WorkerService::GetInstance())));
-  AddFilter(worker_message_filter_);
-  AddFilter(new AppCacheDispatcherHost(
+  child_process_host()->AddFilter(worker_message_filter_);
+  child_process_host()->AddFilter(new AppCacheDispatcherHost(
       resource_context_->appcache_service(), id()));
-  AddFilter(new FileSystemDispatcherHost(
+  child_process_host()->AddFilter(new FileSystemDispatcherHost(
       request_context, resource_context_->file_system_context()));
-  AddFilter(new FileUtilitiesMessageFilter(id()));
-  AddFilter(new BlobMessageFilter(
+  child_process_host()->AddFilter(new FileUtilitiesMessageFilter(id()));
+  child_process_host()->AddFilter(new BlobMessageFilter(
       id(), resource_context_->blob_storage_context()));
-  AddFilter(new MimeRegistryMessageFilter());
-  AddFilter(new DatabaseMessageFilter(
+  child_process_host()->AddFilter(new MimeRegistryMessageFilter());
+  child_process_host()->AddFilter(new DatabaseMessageFilter(
       resource_context_->database_tracker()));
 
   SocketStreamDispatcherHost* socket_stream_dispatcher_host =
       new SocketStreamDispatcherHost(
           new URLRequestContextSelector(request_context), resource_context_);
-  AddFilter(socket_stream_dispatcher_host);
-  AddFilter(new content::WorkerDevToolsMessageFilter(id()));
+  child_process_host()->AddFilter(socket_stream_dispatcher_host);
+  child_process_host()->AddFilter(
+      new content::WorkerDevToolsMessageFilter(id()));
 }
 
 void WorkerProcessHost::CreateWorker(const WorkerInstance& instance) {