Move content's a plugin, ppapi_plugin, utility, and worker subdirectories to the content namespace.

content/plugin/plugin_main_linux.cc

 // Copyright (c) 2011 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 <signal.h>
 #include <string.h>
 #include <sys/types.h>
 #include <syscall.h>
 #include <unistd.h>
 
 #include "build/build_config.h"
 
 // This whole file is only useful on 64-bit architectures.
 #if defined(ARCH_CPU_64_BITS)
 
+namespace content {
+
 namespace {
 
 // Signal handler for SIGILL; see WorkaroundFlashLAHF().
 void SignalHandler(int signum, siginfo_t* info, void* void_context) {
   const char kLAHFInstruction = 0x9f;
   ucontext_t* context = static_cast<ucontext_t*>(void_context);
   greg_t* regs = context->uc_mcontext.gregs;
   char instruction = *reinterpret_cast<char*>(regs[REG_RIP]);
 
   // Check whether this is the kind of SIGILL we care about.
@@ skipping 34 matching lines @@
 // particular circumstance, emulating the instruction, and resuming.
 // This function registers the signal handler.
 void WorkaroundFlashLAHF() {
   struct sigaction action = { { NULL } };
   action.sa_flags = SA_SIGINFO;
   action.sa_sigaction = &SignalHandler;
 
   sigaction(SIGILL, &action, NULL);
 }
 
+}  // namespace content
+
 #endif  // defined(ARCH_CPU_64_BITS)