remove most Isolate::Current asserts

src/debug.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 972 matching lines @@
 
 // Stack allocated class for disabling break.
 class DisableBreak BASE_EMBEDDED {
  public:
   explicit DisableBreak(Isolate* isolate, bool disable_break)
     : isolate_(isolate) {
     prev_disable_break_ = isolate_->debug()->disable_break();
     isolate_->debug()->set_disable_break(disable_break);
   }
   ~DisableBreak() {
-    ASSERT(Isolate::Current() == isolate_);
     isolate_->debug()->set_disable_break(prev_disable_break_);
   }
 
  private:
   Isolate* isolate_;
   // The previous state of the disable break used to restore the value when this
   // object is destructed.
   bool prev_disable_break_;
 };
 
@@ skipping 59 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(MessageDispatchHelperThread);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // ENABLE_DEBUGGER_SUPPORT
 
 #endif  // V8_DEBUG_H_