Linux: fix a bunch of NULL vs. 0 issues spotted by gcc 4.5.

chrome/browser/ppapi_plugin_process_host.cc

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ppapi_plugin_process_host.h"
 
 #include "base/command_line.h"
 #include "base/file_path.h"
 #include "base/process_util.h"
 #include "chrome/browser/renderer_host/render_message_filter.h"
@@ skipping 10 matching lines @@
 
 PpapiPluginProcessHost::~PpapiPluginProcessHost() {
 }
 
 void PpapiPluginProcessHost::Init(const FilePath& path,
                                   IPC::Message* reply_msg) {
   plugin_path_ = path;
   reply_msg_.reset(reply_msg);
 
   if (!CreateChannel()) {
-    ReplyToRenderer(NULL, IPC::ChannelHandle());
+    ReplyToRenderer(base::kNullProcessHandle, IPC::ChannelHandle());
     return;
   }
 
   const CommandLine& browser_command_line = *CommandLine::ForCurrentProcess();
   CommandLine::StringType plugin_launcher =
       browser_command_line.GetSwitchValueNative(switches::kPpapiPluginLauncher);
 
   FilePath exe_path = ChildProcessHost::GetChildPath(plugin_launcher.empty());
   if (exe_path.empty()) {
-    ReplyToRenderer(NULL, IPC::ChannelHandle());
+    ReplyToRenderer(base::kNullProcessHandle, IPC::ChannelHandle());
     return;
   }
 
   CommandLine* cmd_line = new CommandLine(exe_path);
   cmd_line->AppendSwitchASCII(switches::kProcessType,
                               switches::kPpapiPluginProcess);
   cmd_line->AppendSwitchASCII(switches::kProcessChannelID, channel_id());
 
   if (!plugin_launcher.empty())
     cmd_line->PrependWrapper(plugin_launcher);
@@ skipping 33 matching lines @@
   ::DuplicateHandle(::GetCurrentProcess(), filter_->peer_handle(),
                     GetChildProcessHandle(), &plugins_renderer_handle,
                     0, FALSE, DUPLICATE_SAME_ACCESS);
 #elif defined(OS_POSIX)
   base::ProcessHandle plugins_renderer_handle = filter_->peer_handle();
 #endif
 
   PpapiMsg_LoadPlugin* msg = new PpapiMsg_LoadPlugin(
       plugins_renderer_handle, plugin_path_, filter_->render_process_id());
   if (!Send(msg))  // Just send an empty handle on failure.
-    ReplyToRenderer(NULL, IPC::ChannelHandle());
+    ReplyToRenderer(base::kNullProcessHandle, IPC::ChannelHandle());
   // This function will result in OnChannelCreated getting called to finish.
 }
 
 void PpapiPluginProcessHost::OnChannelError() {
   if (reply_msg_.get())
-    ReplyToRenderer(NULL, IPC::ChannelHandle());
+    ReplyToRenderer(base::kNullProcessHandle, IPC::ChannelHandle());
 }
 
 void PpapiPluginProcessHost::OnPluginLoaded(
     const IPC::ChannelHandle& channel_handle) {
   base::ProcessHandle plugin_process = GetChildProcessHandle();
 #if defined(OS_WIN)
   base::ProcessHandle renderers_plugin_handle = NULL;
   ::DuplicateHandle(::GetCurrentProcess(), plugin_process,
                     filter_->peer_handle(), &renderers_plugin_handle,
                     0, FALSE, DUPLICATE_SAME_ACCESS);
 #elif defined(OS_POSIX)
   // Don't need to duplicate anything on POSIX since it's just a PID.
   base::ProcessHandle renderers_plugin_handle = plugin_process;
 #endif
   ReplyToRenderer(renderers_plugin_handle, channel_handle);
 }
 
 void PpapiPluginProcessHost::ReplyToRenderer(
     base::ProcessHandle plugin_handle,
     const IPC::ChannelHandle& channel_handle) {
   DCHECK(reply_msg_.get());
   ViewHostMsg_OpenChannelToPepperPlugin::WriteReplyParams(reply_msg_.get(),
                                                           plugin_handle,
                                                           channel_handle);
   filter_->Send(reply_msg_.release());
 }