PPAPI: Compile out thread checks when pepper threading is turned on.

ppapi/shared_impl/var_tracker.h

 // Copyright (c) 2012 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.
 
 #ifndef PPAPI_SHARED_IMPL_VAR_TRACKER_H_
 #define PPAPI_SHARED_IMPL_VAR_TRACKER_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 15 matching lines @@
 // necessary in the plugin side of the proxy when running out of process. A
 // tracked object is one that the plugin is aware of, but doesn't hold a
 // reference to. This will happen when the plugin is passed an object as an
 // argument from the host (renderer) as an input argument to a sync function,
 // but where ownership is not passed.
 //
 // This class maintains the "track_with_no_reference_count" but doesn't do
 // anything with it other than call virtual functions. The interesting parts
 // are added by the PluginObjectVar derived from this class.
 class PPAPI_SHARED_EXPORT VarTracker
+#ifdef ENABLE_PEPPER_THREADING
+    : NON_EXPORTED_BASE(public base::NonThreadSafeDoNothing) {
+#else
+    // TODO(dmichael): Remove the thread checking when calls are allowed off the
+    // main thread (crbug.com/92909).
     : NON_EXPORTED_BASE(public base::NonThreadSafe) {
+#endif
  public:
   VarTracker();
   virtual ~VarTracker();
 
   // Called by the Var object to add a new var to the tracker.
   int32 AddVar(Var* var);
 
   // Looks up a given var and returns a reference to the Var if it exists.
   // Returns NULL if the var type is not an object we track (POD) or is
   // invalid.
@@ skipping 108 matching lines @@
   // implemented by the Host and Plugin tracker separately, so that it can be
   // a real WebKit ArrayBuffer on the host side.
   virtual ArrayBufferVar* CreateArrayBuffer(uint32 size_in_bytes) = 0;
 
   DISALLOW_COPY_AND_ASSIGN(VarTracker);
 };
 
 }  // namespace ppapi
 
 #endif  // PPAPI_SHARED_IMPL_VAR_TRACKER_H_