Reland 9034035: Make it possible to have 1 PpapiGlobals per thread.

ppapi/proxy/plugin_var_serialization_rules.cc

 // Copyright (c) 2011 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_serialization_rules.h"
 
 #include "base/logging.h"
 #include "ppapi/proxy/plugin_dispatcher.h"
 #include "ppapi/proxy/plugin_globals.h"
 #include "ppapi/proxy/plugin_resource_tracker.h"
@@ skipping 67 matching lines @@
   // Browser calls BeginSendPassRef   3        2            0        1
   // Plugin calls ReceivePassRef      4        1            1        1
   // Browser calls EndSendPassRef     4        1            1        1
   //
   // In example 1 before the send, the plugin has 3 refs which are represented
   // as one ref in the browser (since the plugin only tells the browser when
   // it's refcount goes from 1 -> 0). The initial state is that the browser
   // plugin code started to return a value, which means it gets another ref
   // on behalf of the caller. This needs to be transferred to the plugin and
   // folded in to its set of refs it maintains (with one ref representing all
-  // fo them in the browser).
+  // of them in the browser).
   if (var.type == PP_VARTYPE_OBJECT) {
     DCHECK(dispatcher->IsPlugin());
     return var_tracker_->ReceiveObjectPassRef(
         var, static_cast<PluginDispatcher*>(dispatcher));
   }
 
   // Other types are unchanged.
   return var;
 }
 
@@ skipping 41 matching lines @@
     var_tracker_->ReleaseVar(var);
   }
 }
 
 void PluginVarSerializationRules::ReleaseObjectRef(const PP_Var& var) {
   var_tracker_->ReleaseVar(var);
 }
 
 }  // namespace proxy
 }  // namespace ppapi