Leaving a generator via an exception causes it to close

src/runtime/runtime.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_RUNTIME_RUNTIME_H_
 #define V8_RUNTIME_RUNTIME_H_
 
 #include "src/allocation.h"
 #include "src/objects.h"
 #include "src/zone.h"
@@ skipping 460 matching lines @@
                                                              \
   F(NewArguments, 1, 1) /* TODO(turbofan): Only temporary */ \
   F(NewSloppyArguments, 3, 1)                                \
   F(NewStrictArguments, 3, 1)                                \
                                                              \
   /* Harmony generators */                                   \
   F(CreateJSGeneratorObject, 0, 1)                           \
   F(SuspendJSGeneratorObject, 1, 1)                          \
   F(ResumeJSGeneratorObject, 3, 1)                           \
   F(ThrowGeneratorStateError, 1, 1)                          \
+  F(GeneratorClose, 1, 1)                                    \
                                                              \
   /* Arrays */                                               \
   F(ArrayConstructor, -1, 1)                                 \
   F(InternalArrayConstructor, -1, 1)                         \
                                                              \
   /* Literals */                                             \
   F(MaterializeRegExpLiteral, 4, 1)                          \
   F(CreateObjectLiteral, 4, 1)                               \
   F(CreateArrayLiteral, 4, 1)                                \
   F(CreateArrayLiteralStubBailout, 3, 1)                     \
@@ skipping 397 matching lines @@
 class AllocateTargetSpace : public BitField<AllocationSpace, 1, 3> {};
 
 class DeclareGlobalsEvalFlag : public BitField<bool, 0, 1> {};
 class DeclareGlobalsNativeFlag : public BitField<bool, 1, 1> {};
 class DeclareGlobalsStrictMode : public BitField<StrictMode, 2, 1> {};
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_RUNTIME_RUNTIME_H_