Make ChildProcessHost be used through an interface in content/public, instead of by inheritence.

content/browser/ppapi_plugin_process_host.cc

Index: content/browser/ppapi_plugin_process_host.cc
===================================================================
--- content/browser/ppapi_plugin_process_host.cc	(revision 112775)
+++ content/browser/ppapi_plugin_process_host.cc	(working copy)
@@ -11,7 +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_host_impl.h"
 #include "content/common/child_process_messages.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/pepper_plugin_info.h"
@@ -20,6 +20,9 @@
 #include "net/base/network_change_notifier.h"
 #include "ppapi/proxy/ppapi_messages.h"
 
+using content::ChildProcessHost;
+using content::ChildProcessHostImpl;
+
 class PpapiPluginProcessHost::PluginNetworkObserver
     : public net::NetworkChangeNotifier::IPAddressObserver,
       public net::NetworkChangeNotifier::OnlineStateObserver {
@@ -85,7 +88,7 @@
 }
 
 void PpapiPluginProcessHost::OpenChannelToPlugin(Client* client) {
-  if (child_process_host()->opening_channel()) {
+  if (child_process_host()->IsChannelOpening()) {
     // 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.
@@ -102,14 +105,14 @@
       filter_(new PepperMessageFilter(host_resolver)),
       network_observer_(new PluginNetworkObserver(this)),
       is_broker_(false),
-      process_id_(ChildProcessHost::GenerateChildProcessUniqueId()) {
+      process_id_(ChildProcessHostImpl::GenerateChildProcessUniqueId()) {
   child_process_host()->AddFilter(filter_.get());
 }
 
 PpapiPluginProcessHost::PpapiPluginProcessHost()
     : BrowserChildProcessHost(content::PROCESS_TYPE_PPAPI_BROKER),
       is_broker_(true),
-      process_id_(ChildProcessHost::GenerateChildProcessUniqueId()) {
+      process_id_(ChildProcessHostImpl::GenerateChildProcessUniqueId()) {
 }
 
 bool PpapiPluginProcessHost::Init(const content::PepperPluginInfo& info) {
@@ -120,7 +123,8 @@
     set_name(UTF8ToUTF16(info.name));
   }
 
-  if (!child_process_host()->CreateChannel())
+  std::string channel_id = child_process_host()->CreateChannel();
+  if (channel_id.empty())
     return false;
 
   const CommandLine& browser_command_line = *CommandLine::ForCurrentProcess();
@@ -141,8 +145,7 @@
   cmd_line->AppendSwitchASCII(switches::kProcessType,
                               is_broker_ ? switches::kPpapiBrokerProcess
                                          : switches::kPpapiPluginProcess);
-  cmd_line->AppendSwitchASCII(switches::kProcessChannelID,
-                              child_process_host()->channel_id());
+  cmd_line->AppendSwitchASCII(switches::kProcessChannelID, channel_id);
 
   // These switches are forwarded to both plugin and broker pocesses.
   static const char* kCommonForwardSwitches[] = {