Add window manager component.

wm/shell/shell_main.cc

Index: wm/shell/shell_main.cc
diff --git a/content/shell/shell_content_main.cc b/wm/shell/shell_main.cc
similarity index 53%
copy from content/shell/shell_content_main.cc
copy to wm/shell/shell_main.cc
index 79931987f4bd4bac68ee22dbac28608a21303d02..0ea967a73b574a62590c20b1de751d82a9125113 100644
--- a/content/shell/shell_content_main.cc
+++ b/wm/shell/shell_main.cc
@@ -2,15 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "content/shell/shell_content_main.h"
-
 #include "content/public/app/content_main.h"
-#include "content/shell/shell_main_delegate.h"
+#include "wm/shell/content_client/shell_main_delegate.h"
 
-#if defined(OS_MACOSX)
-int ContentMain(int argc,
-                const char** argv) {
-  content::ShellMainDelegate delegate;
+int main(int argc, const char** argv) {
+  wm::shell::ShellMainDelegate delegate;
   return content::ContentMain(argc, argv, &delegate);
 }
-#endif  // OS_MACOSX