Remove obsolete methods from IPC::Channel and related classes.

ipc/ipc_descriptors.h

Index: ipc/ipc_descriptors.h
diff --git a/ipc/ipc_descriptors.h b/ipc/ipc_descriptors.h
index 9dcff8ceb1394879fe4077321a1dee97af00e6b7..7a4a7b19a5c519701911767d685fa9ef73636f9d 100644
--- a/ipc/ipc_descriptors.h
+++ b/ipc/ipc_descriptors.h
@@ -8,11 +8,8 @@
 // This is a list of global descriptor keys to be used with the
 // base::GlobalDescriptors object (see base/posix/global_descriptors.h)
 enum {
-  kPrimaryIPCChannel = 0,
-  kStatsTableSharedMemFd,
-
   // The first key that can be use to register descriptors.
-  kIPCDescriptorMax
+  kIPCDescriptorMax = 0
 };
 
 #endif  // IPC_IPC_DESCRIPTORS_H_