Refactoring: Make IPC::Channel::TakeClientFileDescriptor() a ScopedFD.

base/file_descriptor_posix.h

Index: base/file_descriptor_posix.h
diff --git a/base/file_descriptor_posix.h b/base/file_descriptor_posix.h
index c730be65f749473bf1943d14bca0334fcc6bab78..376ad39e307addafe0cd7395d8578c3956a3a621 100644
--- a/base/file_descriptor_posix.h
+++ b/base/file_descriptor_posix.h
@@ -6,6 +6,7 @@
 #define BASE_FILE_DESCRIPTOR_POSIX_H_
 
 #include "base/files/file.h"
+#include "base/files/scoped_file.h"
 
 namespace base {
 
@@ -24,6 +25,7 @@ struct FileDescriptor {
   }
 
   FileDescriptor(File file) : fd(file.TakePlatformFile()), auto_close(true) {}
+  explicit FileDescriptor(ScopedFD fd) : fd(fd.release()), auto_close(true) {}
 
   bool operator==(const FileDescriptor& other) const {
     return (fd == other.fd && auto_close == other.auto_close);