Make the v8 Isolate used in the proxy resolver explicit.

net/proxy/proxy_resolver_v8.h

 // 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.
 
 #ifndef NET_PROXY_PROXY_RESOLVER_V8_H_
 #define NET_PROXY_PROXY_RESOLVER_V8_H_
 
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "net/base/net_export.h"
 #include "net/proxy/proxy_resolver.h"
 
+namespace v8 {
+class Isolate;
+}  // namespace v8
+
 namespace net {
 
 class ProxyResolverJSBindings;
 
 // Implementation of ProxyResolver that uses V8 to evaluate PAC scripts.
 //
 // ----------------------------------------------------------------------------
 // !!! Important note on threading model:

[eroman, 2013/01/18 19:21:14]

Please update this comment.

[Sven Panne, 2013/01/21 08:50:06]

This comment is still OK. The v8_default_isolate below *is* the only instance of
V8 the comment is talking about. Do you think that this should be added or what
else is missing/wrong?

 // ----------------------------------------------------------------------------
 // There can be only one instance of V8 running at a time. To enforce this
 // constraint, ProxyResolverV8 holds a v8::Locker during execution. Therefore
 // it is OK to run multiple instances of ProxyResolverV8 on different threads,
 // since only one will be running inside V8 at a time.
 //
 // It is important that *ALL* instances of V8 in the process be using
 // v8::Locker. If not there can be race conditions between the non-locked V8
 // instances and the locked V8 instances used by ProxyResolverV8 (assuming they
 // run on different threads).
 //
 // This is the case with the V8 instance used by chromium's renderer -- it runs
 // on a different thread from ProxyResolver (renderer thread vs PAC thread),
 // and does not use locking since it expects to be alone.
 class NET_EXPORT_PRIVATE ProxyResolverV8 : public ProxyResolver {
  public:
   // Constructs a ProxyResolverV8 with custom bindings. ProxyResolverV8 takes
   // ownership of |custom_js_bindings| and deletes it when ProxyResolverV8
   // is destroyed.
-  explicit ProxyResolverV8(ProxyResolverJSBindings* custom_js_bindings);
+  ProxyResolverV8(ProxyResolverJSBindings* custom_js_bindings,
+                  v8::Isolate* v8_default_isolate);
 
   virtual ~ProxyResolverV8();
 
   ProxyResolverJSBindings* js_bindings() const { return js_bindings_.get(); }
 
   // ProxyResolver implementation:
   virtual int GetProxyForURL(const GURL& url,
                              ProxyInfo* results,
                              const net::CompletionCallback& /*callback*/,
                              RequestHandle* /*request*/,
@@ skipping 11 matching lines @@
 
  private:
   // Context holds the Javascript state for the most recently loaded PAC
   // script. It corresponds with the data from the last call to
   // SetPacScript().
   class Context;
   scoped_ptr<Context> context_;
 
   scoped_ptr<ProxyResolverJSBindings> js_bindings_;
 
+  v8::Isolate* v8_default_isolate_;
+
   DISALLOW_COPY_AND_ASSIGN(ProxyResolverV8);
 };
 
 }  // namespace net
 
 #endif  // NET_PROXY_PROXY_RESOLVER_V8_H_