Revert 189518 "PPAPI: Remove threading options; it's always on"

trunk/src/ppapi/proxy/plugin_var_tracker.cc

 // 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.
 
 #include "ppapi/proxy/plugin_var_tracker.h"
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/singleton.h"
 #include "ppapi/c/dev/ppp_class_deprecated.h"
 #include "ppapi/c/ppb_var.h"
@@ skipping 13 matching lines @@
 }
 
 bool PluginVarTracker::HostVar::operator<(const HostVar& other) const {
   if (dispatcher < other.dispatcher)
     return true;
   if (other.dispatcher < dispatcher)
     return false;
   return host_object_id < other.host_object_id;
 }
 
-PluginVarTracker::PluginVarTracker() : VarTracker(THREAD_SAFE) {
+PluginVarTracker::PluginVarTracker() {
 }
 
 PluginVarTracker::~PluginVarTracker() {
 }
 
 PP_Var PluginVarTracker::ReceiveObjectPassRef(const PP_Var& host_var,
                                               PluginDispatcher* dispatcher) {
-  CheckThreadingPreconditions();
+  DCHECK(CalledOnValidThread());
   DCHECK(host_var.type == PP_VARTYPE_OBJECT);
 
   // Get the object.
   scoped_refptr<ProxyObjectVar> object(
       FindOrMakePluginVarFromHostVar(host_var, dispatcher));
 
   // Actually create the PP_Var, this will add all the tracking info but not
   // adjust any refcounts.
   PP_Var ret = GetOrCreateObjectVarID(object.get());
 
   VarInfo& info = GetLiveVar(ret)->second;
   if (info.ref_count > 0) {
     // We already had a reference to it before. That means the renderer now has
     // two references on our behalf. We want to transfer that extra reference
     // to our list. This means we addref in the plugin, and release the extra
     // one in the renderer.
     SendReleaseObjectMsg(*object);
   }
   info.ref_count++;
   return ret;
 }
 
 PP_Var PluginVarTracker::TrackObjectWithNoReference(
     const PP_Var& host_var,
     PluginDispatcher* dispatcher) {
-  CheckThreadingPreconditions();
+  DCHECK(CalledOnValidThread());
   DCHECK(host_var.type == PP_VARTYPE_OBJECT);
 
   // Get the object.
   scoped_refptr<ProxyObjectVar> object(
       FindOrMakePluginVarFromHostVar(host_var, dispatcher));
 
   // Actually create the PP_Var, this will add all the tracking info but not
   // adjust any refcounts.
   PP_Var ret = GetOrCreateObjectVarID(object.get());
 
   VarInfo& info = GetLiveVar(ret)->second;
   info.track_with_no_reference_count++;
   return ret;
 }
 
 void PluginVarTracker::StopTrackingObjectWithNoReference(
     const PP_Var& plugin_var) {
-  CheckThreadingPreconditions();
+  DCHECK(CalledOnValidThread());
   DCHECK(plugin_var.type == PP_VARTYPE_OBJECT);
 
   VarMap::iterator found = GetLiveVar(plugin_var);
   if (found == live_vars_.end()) {
     NOTREACHED();
     return;
   }
 
   DCHECK(found->second.track_with_no_reference_count > 0);
   found->second.track_with_no_reference_count--;
   DeleteObjectInfoIfNecessary(found);
 }
 
 PP_Var PluginVarTracker::GetHostObject(const PP_Var& plugin_object) const {
-  CheckThreadingPreconditions();
+  DCHECK(CalledOnValidThread());
+
   if (plugin_object.type != PP_VARTYPE_OBJECT) {
     NOTREACHED();
     return PP_MakeUndefined();
   }
 
   Var* var = GetVar(plugin_object);
   ProxyObjectVar* object = var->AsProxyObjectVar();
   if (!object) {
     NOTREACHED();
     return PP_MakeUndefined();
   }
 
   // Make a var with the host ID.
   PP_Var ret = { PP_VARTYPE_OBJECT };
   ret.value.as_id = object->host_var_id();
   return ret;
 }
 
 PluginDispatcher* PluginVarTracker::DispatcherForPluginObject(
     const PP_Var& plugin_object) const {
-  CheckThreadingPreconditions();
+  DCHECK(CalledOnValidThread());
+
   if (plugin_object.type != PP_VARTYPE_OBJECT)
     return NULL;
 
   VarMap::const_iterator found = GetLiveVar(plugin_object);
   if (found == live_vars_.end())
     return NULL;
 
   ProxyObjectVar* object = found->second.var->AsProxyObjectVar();
   if (!object)
     return NULL;
   return object->dispatcher();
 }
 
 void PluginVarTracker::ReleaseHostObject(PluginDispatcher* dispatcher,
                                          const PP_Var& host_object) {
-  CheckThreadingPreconditions();
+  DCHECK(CalledOnValidThread());
   DCHECK(host_object.type == PP_VARTYPE_OBJECT);
 
   // Convert the host object to a normal var valid in the plugin.
   HostVarToPluginVarMap::iterator found = host_var_to_plugin_var_.find(
       HostVar(dispatcher, static_cast<int32>(host_object.value.as_id)));
   if (found == host_var_to_plugin_var_.end()) {
     NOTREACHED();
     return;
   }
 
@@ skipping 235 matching lines @@
     int id,
     PP_Instance instance,
     base::SharedMemoryHandle* handle,
     uint32* size_in_bytes) {
   NOTREACHED();
   return false;
 }
 
 }  // namesace proxy
 }  // namespace ppapi