Linux Sandbox: split the GPU policies to their own file.

content/common/sandbox_linux/sandbox_linux.h

Index: content/common/sandbox_linux/sandbox_linux.h
diff --git a/content/common/sandbox_linux.h b/content/common/sandbox_linux/sandbox_linux.h
similarity index 96%
rename from content/common/sandbox_linux.h
rename to content/common/sandbox_linux/sandbox_linux.h
index 5101f23df61298433d165bc84661dd8b23ba0442..9afca59b25a7c6989a2f2cb6748f8a8f2adbe6bf 100644
--- a/content/common/sandbox_linux.h
+++ b/content/common/sandbox_linux/sandbox_linux.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CONTENT_COMMON_SANDBOX_LINUX_H_
-#define CONTENT_COMMON_SANDBOX_LINUX_H_
+#ifndef CONTENT_COMMON_SANDBOX_LINUX_SANDBOX_LINUX_H_
+#define CONTENT_COMMON_SANDBOX_LINUX_SANDBOX_LINUX_H_
 
 #include <string>
 
@@ -104,5 +104,4 @@ class LinuxSandbox {
 
 }  // namespace content
 
-#endif  // CONTENT_COMMON_SANDBOX_LINUX_H_
-
+#endif  // CONTENT_COMMON_SANDBOX_LINUX_SANDBOX_LINUX_H_