Create a new xpcom obsolete library (and component library).

Moved nsFileSpec and related classes into this obsolete library.
  Moved nsRegistry and related libreg functionality into the obsolete library.

Updated many callers using the obsolete nsFile spec to use nsIFile and Necko to do file IO.

Combined the following DLLs (source -> dest)
  uriloader -> docshell
  shistory -> docshell
  jsurl -> jsdom
  gkview -> gklayout

Moved nsAdapterEnumerator out of xpcom/ds and into mailnews, since they're the only consumer

Modifed the xpt_link tool so that you can specify a �only include� cid list that can mask CID�s that you are not interested in.

Added build options:
Prevent the building of xpinstall (--disable-xpinstall)
Prevent the building js component loader (--disable-jsloader)
A build option to only build a single profile (--enable-single-profile)
A build flag to only built the required xpfe components (--disable-xpfe-components).

Removal or hiding of unused functions and classes including nsEscape*, nsDequeIterator, nsRecyclingAllocatorImpl, nsDiscriminatedUnion, nsOpaqueKey, nsCRT::strlen, NS_NewCommandLineService

Bug 194240, r/sr = darin, alec.

docshell/base/nsDocShell.cpp

@@ -59,6 +59,7 @@
 #include "nsContentPolicyUtils.h" // NS_CheckContentLoadPolicy(...)
 #include "nsICategoryManager.h"
 #include "nsXPCOMCID.h"
+#include "nsISeekableStream.h"
 
 // we want to explore making the document own the load group
 // so we can associate the document URI with the load group.
@@ -83,7 +84,6 @@
 #include "nsIWebProgress.h"
 #include "nsILayoutHistoryState.h"
 #include "nsITimer.h"
-#include "nsIFileStream.h"
 #include "nsISHistoryInternal.h"
 #include "nsIPrincipal.h"
 #include "nsIHistoryEntry.h"