Reland 24052 - Require V8 to be explicitly initialized before an Isolate is created

src/isolate.h

Index: src/isolate.h
diff --git a/src/isolate.h b/src/isolate.h
index 28a45da9794a5a3d0547ee7cd3096c3a657bec5b..24d4b0898de5d5cdb36327f12d24c3283b21e355 100644
--- a/src/isolate.h
+++ b/src/isolate.h
@@ -466,17 +466,17 @@ class Isolate {
     kIsolateAddressCount
   };
 
+  static void InitializeOncePerProcess();
+
   // Returns the PerIsolateThreadData for the current thread (or NULL if one is
   // not currently set).
   static PerIsolateThreadData* CurrentPerIsolateThreadData() {
-    EnsureInitialized();
     return reinterpret_cast<PerIsolateThreadData*>(
         base::Thread::GetThreadLocal(per_isolate_thread_data_key_));
   }
 
   // Returns the isolate inside which the current thread is running.
   INLINE(static Isolate* Current()) {
-    EnsureInitialized();
     Isolate* isolate = reinterpret_cast<Isolate*>(
         base::Thread::GetExistingThreadLocal(isolate_key_));
     DCHECK(isolate != NULL);
@@ -484,7 +484,6 @@ class Isolate {
   }
 
   INLINE(static Isolate* UncheckedCurrent()) {
-    EnsureInitialized();
     return reinterpret_cast<Isolate*>(
         base::Thread::GetThreadLocal(isolate_key_));
   }
@@ -529,13 +528,11 @@ class Isolate {
   // Used internally for V8 threads that do not execute JavaScript but still
   // are part of the domain of an isolate (like the context switcher).
   static base::Thread::LocalStorageKey isolate_key() {
-    EnsureInitialized();
     return isolate_key_;
   }
 
   // Returns the key used to store process-wide thread IDs.
   static base::Thread::LocalStorageKey thread_id_key() {
-    EnsureInitialized();
     return thread_id_key_;
   }
 
@@ -1110,9 +1107,9 @@ class Isolate {
   void SetUseCounterCallback(v8::Isolate::UseCounterCallback callback);
   void CountUsage(v8::Isolate::UseCounterFeature feature);
 
- private:
-  static void EnsureInitialized();
+  static Isolate* NewForTesting() { return new Isolate(); }
 
+ private:
   Isolate();
 
   friend struct GlobalState;
@@ -1171,8 +1168,7 @@ class Isolate {
     DISALLOW_COPY_AND_ASSIGN(EntryStackItem);
   };
 
-  // This mutex protects highest_thread_id_ and thread_data_table_.
-  static base::LazyMutex process_wide_mutex_;
+  static base::LazyMutex thread_data_table_mutex_;
 
   static base::Thread::LocalStorageKey per_isolate_thread_data_key_;
   static base::Thread::LocalStorageKey isolate_key_;