Separates ipc code from common (http://crbug.com/16829)

chrome/common/ipc_maybe.h

Index: chrome/common/ipc_maybe.h
diff --git a/chrome/common/ipc_maybe.h b/chrome/common/ipc_maybe.h
deleted file mode 100644
index de45dc02b43b67c0c28355130e1bbf8d33d1c842..0000000000000000000000000000000000000000
--- a/chrome/common/ipc_maybe.h
+++ /dev/null
@@ -1,19 +0,0 @@
-#ifndef CHROME_COMMON_MAYBE_H_
-#define CHROME_COMMON_MAYBE_H_
-
-namespace IPC {
-
-// The Maybe type can be used to avoid serialising a type when it's invalid.
-// This is most useful in conjunction with FileDescriptor, as there's no
-// possible invalid value which can be serialised (one can type to use -1, but
-// the IPC channel will fail). It may also be useful if the invalid value is
-// otherwise expensive to serialise.
-template<typename A>
-struct Maybe {
-  bool valid;
-  A value;
-};
-
-}  // namespace IPC
-
-#endif  // CHROME_COMMON_MAYBE_H_