Remove unused StubType's, freeing 2 bits in Code objects.

src/objects.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 5015 matching lines @@
 
   // No more than 16 kinds. The value is currently encoded in four bits in
   // Flags.
   STATIC_ASSERT(NUMBER_OF_KINDS <= 16);
 
   static const char* Kind2String(Kind kind);
 
   // Types of stubs.
   enum StubType {
     NORMAL,
-    FIELD,
-    CONSTANT,
-    CALLBACKS,
-    INTERCEPTOR,
-    TRANSITION,
-    NONEXISTENT
+    FAST
   };
 
   typedef int ExtraICState;
 
   static const ExtraICState kNoExtraICState = 0;
 
   static const int kPrologueOffsetNotSet = -1;
 
 #ifdef ENABLE_DISASSEMBLER
   // Printing
@@ skipping 405 matching lines @@
   class FullCodeFlagsHasDeoptimizationSupportField:
       public BitField<bool, 0, 1> {};  // NOLINT
   class FullCodeFlagsHasDebugBreakSlotsField: public BitField<bool, 1, 1> {};
   class FullCodeFlagsIsCompiledOptimizable: public BitField<bool, 2, 1> {};
 
   static const int kAllowOSRAtLoopNestingLevelOffset = kFullCodeFlags + 1;
   static const int kProfilerTicksOffset = kAllowOSRAtLoopNestingLevelOffset + 1;
 
   // Flags layout.  BitField<type, shift, size>.
   class ICStateField: public BitField<InlineCacheState, 0, 3> {};
-  class TypeField: public BitField<StubType, 3, 3> {};
+  class TypeField: public BitField<StubType, 3, 1> {};
   class CacheHolderField: public BitField<InlineCacheHolderFlag, 6, 1> {};
   class KindField: public BitField<Kind, 7, 4> {};
   class IsPregeneratedField: public BitField<bool, 11, 1> {};
   class ExtraICStateField: public BitField<ExtraICState, 12, 5> {};
   class ExtendedExtraICStateField: public BitField<ExtraICState, 12,
       PlatformSmiTagging::kSmiValueSize - 12 + 1> {};  // NOLINT
   STATIC_ASSERT(ExtraICStateField::kShift == ExtendedExtraICStateField::kShift);
 
   // KindSpecificFlags1 layout (STUB and OPTIMIZED_FUNCTION)
   static const int kStackSlotsFirstBit = 0;
@@ skipping 5092 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_