Make the v8 Isolate used in the proxy resolver explicit.

chrome/browser/io_thread.cc

Index: chrome/browser/io_thread.cc
diff --git a/chrome/browser/io_thread.cc b/chrome/browser/io_thread.cc
index 025fbe518b0de6a65608d38aea4fd0c5ab35ad7f..95e08f0b2b64741ba3ee8cbacb68b3bf87b6217c 100644
--- a/chrome/browser/io_thread.cc
+++ b/chrome/browser/io_thread.cc
@@ -70,6 +70,10 @@
 #include "net/ocsp/nss_ocsp.h"
 #endif
 
+#if !defined(OS_IOS)
+#include "net/proxy/proxy_resolver_v8.h"
+#endif
+
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/proxy_config_service_impl.h"
 #endif  // defined(OS_CHROMEOS)
@@ -369,6 +373,9 @@ IOThread::IOThread(
       sdch_manager_(NULL),
       is_spdy_disabled_by_policy_(false),
       ALLOW_THIS_IN_INITIALIZER_LIST(weak_factory_(this)) {
+#if !defined(OS_IOS)
+  net::ProxyResolverV8::RememberDefaultIsolate();

[John Knottenbelt, 2013/02/01 15:39:33]

On downstream Chrome on Android, this function asserted because V8 hasn't been
initialised yet. Perhaps we are missing some initialisation downstream?

Where does the initialisation happen upstream?

[Sven Panne, 2013/02/01 15:52:28]

RememberDefaultIsolate() has to be called exactly once from the main thread
(i.e. the 'int main(argc, argv)' one in C-speak) before any calls to the v8
proxy resolver. Do *not* call RememberDefaultIsolate() in some kind of static
global initializer, because this would result in undefined behaviour (because v8
uses a such an initializer itself :-P ).

+#endif
   // We call RegisterPrefs() here (instead of inside browser_prefs.cc) to make
   // sure that everything is initialized in the right order.
   //