Build browser/sync files by default using a stubbed-out syncapi...

chrome/browser/sync/engine/syncapi.h

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file defines the "sync API", an interface to the syncer
 // backend that exposes (1) the core functionality of maintaining a consistent
 // local snapshot of a hierarchical object set; (2) a means to transactionally
 // access and modify those objects; (3) a means to control client/server
 // synchronization tasks, namely: pushing local object modifications to a
 // server, pulling nonlocal object modifications from a server to this client,
@@ skipping 33 matching lines @@
 typedef wchar_t sync_char16;
 #else
 typedef uint16 sync_char16;
 #endif
 
 // The MSVC compiler for Windows requires that any classes exported by, or
 // imported from, a dynamic library be decorated with the following fanciness.
 #if (defined(OS_WIN) || defined(OS_WINDOWS))
 #if COMPILING_SYNCAPI_LIBRARY
 #define SYNC_EXPORT __declspec(dllexport)
+#elif COMPILING_SYNCAPI_STUB
+#define SYNC_EXPORT
 #else
 #define SYNC_EXPORT __declspec(dllimport)
 #endif
 #else
 #define SYNC_EXPORT
 #endif  // OS_WIN || OS_WINDOWS
 
 // Forward declarations of internal class types so that sync API objects
 // may have opaque pointers to these types.
 namespace syncable {
@@ skipping 636 matching lines @@
   // Subclasses should implement to invoke DoWork on |visitor| once on a thread
   // appropriate for data model modifications.
   // While it doesn't hurt, the impl does not need to be re-entrant (for now).
   // Note: |visitor| is owned by caller.
   virtual void CallDoWorkFromModelSafeThreadAndWait(Visitor* visitor) = 0;
 };
 
 }  // namespace sync_api
 
 #endif  // CHROME_BROWSER_SYNC_ENGINE_SYNCAPI_H_