Use an explicit PID for duplicating Pepper handles rather than the Channel's.

ppapi/proxy/proxy_channel.cc

Index: ppapi/proxy/proxy_channel.cc
diff --git a/ppapi/proxy/proxy_channel.cc b/ppapi/proxy/proxy_channel.cc
index d1c47a5fbec8596471323b6be2802ef0d1eb1679..81eb9a45553ca6629a8e2601d0cb3701eff9ea30 100644
--- a/ppapi/proxy/proxy_channel.cc
+++ b/ppapi/proxy/proxy_channel.cc
@@ -4,6 +4,8 @@
 
 #include "ppapi/proxy/proxy_channel.h"
 
+#include "base/logging.h"
+#include "base/process_util.h"
 #include "ipc/ipc_platform_file.h"
 #include "ipc/ipc_test_sink.h"
 
@@ -16,6 +18,7 @@ namespace proxy {
 
 ProxyChannel::ProxyChannel()
     : delegate_(NULL),
+      peer_pid_(base::kNullProcessId),
       test_sink_(NULL) {
 }
 
@@ -24,9 +27,11 @@ ProxyChannel::~ProxyChannel() {
 }
 
 bool ProxyChannel::InitWithChannel(Delegate* delegate,
+                                   base::ProcessId peer_pid,
                                    const IPC::ChannelHandle& channel_handle,
                                    bool is_client) {
   delegate_ = delegate;
+  peer_pid_ = peer_pid;
   IPC::Channel::Mode mode = is_client ? IPC::Channel::MODE_CLIENT
                                       : IPC::Channel::MODE_SERVER;
   channel_.reset(new IPC::SyncChannel(channel_handle, mode, this,
@@ -38,6 +43,9 @@ bool ProxyChannel::InitWithChannel(Delegate* delegate,
 void ProxyChannel::InitWithTestSink(IPC::TestSink* test_sink) {
   DCHECK(!test_sink_);
   test_sink_ = test_sink;
+#if !defined(OS_NACL)
+  peer_pid_ = base::GetCurrentProcId();
+#endif
 }
 
 void ProxyChannel::OnChannelError() {
@@ -65,7 +73,8 @@ IPC::PlatformFileForTransit ProxyChannel::ShareHandleWithRemote(
     }
     return IPC::InvalidPlatformFileForTransit();
   }
-  return delegate_->ShareHandleWithRemote(handle, *channel_,
+  DCHECK(peer_pid_ != base::kNullProcessId);
+  return delegate_->ShareHandleWithRemote(handle, peer_pid_,
                                           should_close_source);
 }