Add ShellIntegration::ActivateMetroChrome, which launches Chrome in metro-mode on Windows 8.

chrome/app/metro_driver_win.cc

 // Copyright (c) 2012 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 "metro_driver_win.h"
 
 #include <string.h>
 
 #include "chrome/app/client_util.h"
+#include "chrome/common/chrome_constants.h"
 
 namespace {
-// The windows 8 metro driver dll name and entry point.
-const wchar_t kMetroDriverDll[] = L"metro_driver.dll";
 // This environment variable controls the loading of the metro driver DLL.
 const char* kMetroModeEnvVar = "CHROME_METRO_DLL";
 
 typedef int (*InitMetro)(LPTHREAD_START_ROUTINE thread_proc, void* context);
 
 struct Context {
   MetroDriver::MainFn fn;
   HINSTANCE instance;
 };
 
@@ skipping 11 matching lines @@
     return;
   // The metro activation always has the |ServerName| parameter. If we dont
   // see it, we are being launched in desktop mode.
   if (!wcsstr(::GetCommandLineW(), L" -ServerName:DefaultBrowserServer")) {
     ::SetEnvironmentVariableA(kMetroModeEnvVar, "0");
     return;
   }
   // We haven't tried to load the metro driver, this probably means we are the
   // browser. Find it or not we set the environment variable because we don't
   // want to keep trying in the child processes.
-  HMODULE metro_dll = ::LoadLibraryW(kMetroDriverDll);
+  HMODULE metro_dll = ::LoadLibraryW(chrome::kMetroDriverDll);
   if (!metro_dll) {
     // It is not next to the build output, so this must be an actual deployment
     // and in that case we need the mainloader to find the current version
     // directory.
     MainDllLoader* loader = MakeMainDllLoader();
     std::wstring version = loader->GetVersion();
     delete loader;
     if (!version.empty()) {
       std::wstring exe_path(GetExecutablePath());
-      exe_path.append(version).append(L"\\").append(kMetroDriverDll);
+      exe_path.append(version).append(L"\\").append(chrome::kMetroDriverDll);
       metro_dll = ::LoadLibraryW(exe_path.c_str());
     }
   }
   // We set the environment variable always, so we don't keep trying in
   // the child processes.
   ::SetEnvironmentVariableA(kMetroModeEnvVar, metro_dll ? "1" : "0");
   if (!metro_dll)
     return;
   init_metro_fn_ = ::GetProcAddress(metro_dll, "InitMetro");
 }
 
 int MetroDriver::RunInMetro(HINSTANCE instance, MainFn main_fn) {
   Context* context = new Context;
   context->fn = main_fn;
   context->instance = instance;
 
   return reinterpret_cast<InitMetro>(init_metro_fn_)(&MainThread, context);
 }