Refactor the Heap into ThreadHeap to prepare for per thread heaps

third_party/WebKit/Source/platform/heap/SafePoint.cpp

Index: third_party/WebKit/Source/platform/heap/SafePoint.cpp
diff --git a/third_party/WebKit/Source/platform/heap/SafePoint.cpp b/third_party/WebKit/Source/platform/heap/SafePoint.cpp
index c0574503a1642e397c63a2361cc0987d09f5ae1f..5fecf425165e05ee69817eb1c5f4627fe69e1b5b 100644
--- a/third_party/WebKit/Source/platform/heap/SafePoint.cpp
+++ b/third_party/WebKit/Source/platform/heap/SafePoint.cpp
@@ -45,6 +45,9 @@ bool SafePointBarrier::parkOthers()
         if (state == current)
             continue;
 
+        if (state->isolated())
+            continue;

[haraken, 2015/11/30 02:54:42]

Instead of making this change, we should not add the isolated thread to
ThreadState::attachedThreads() in the first place.

[keishi, 2016/01/06 05:35:33]

Done.

+
         for (auto& interruptor : state->interruptors())
             interruptor->requestInterrupt();
     }