Fix multiple V8::Dispose calls since r16563.

src/v8.cc

Index: src/v8.cc
diff --git a/src/v8.cc b/src/v8.cc
index d9ce8404acddea3391c511ee03ce20e475a27055..c4ce0629c8021b89d39f59c8703dc64371330bb8 100644
--- a/src/v8.cc
+++ b/src/v8.cc
@@ -63,8 +63,8 @@ bool V8::Initialize(Deserializer* des) {
 
   // The current thread may not yet had entered an isolate to run.
   // Note the Isolate::Current() may be non-null because for various
-  // initialization purposes an initializing thread may be assigned an isolate
-  // but not actually enter it.
+  // initialization purposes an initializing thread may be assigned an
+  // isolate but not actually enter it.
   if (i::Isolate::CurrentPerIsolateThreadData() == NULL) {
     i::Isolate::EnterDefaultIsolate();
   }
@@ -84,6 +84,15 @@ bool V8::Initialize(Deserializer* des) {
 
 
 void V8::TearDown() {
+  // The current thread may not yet had entered an isolate to run or may
+  // have already disposed the entered isolated before.
+  // Note the Isolate::Current() may be non-null because for various
+  // initialization purposes an initializing thread may be assigned an
+  // isolate but not actually enter it.
+  if (i::Isolate::CurrentPerIsolateThreadData() == NULL) {
+    return;
+  }
+
   Isolate* isolate = Isolate::Current();
   ASSERT(isolate->IsDefaultIsolate());
   if (!isolate->IsInitialized()) return;
@@ -91,6 +100,7 @@ void V8::TearDown() {
   // The isolate has to be torn down before clearing the LOperand
   // caches so that the optimizing compiler thread (if running)
   // doesn't see an inconsistent view of the lithium instructions.
+  Isolate::SetIsolateThreadLocals(isolate, NULL);

[Sven Panne, 2013/09/06 10:48:27]

This looks a bit strange, but to be honest, I don't have a clue if/how/where we
deallocate the TLS data, so this might be OK.

   isolate->TearDown();
   delete isolate;