Fix secondary stub cache and add a test for the stub cache lookups.

src/v8-counters.h

 // Copyright 2011 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 180 matching lines @@
   SC(call_const_fast_api, V8.CallConstFastApi)                        \
   SC(call_const_interceptor, V8.CallConstInterceptor)                 \
   SC(call_const_interceptor_fast_api, V8.CallConstInterceptorFastApi) \
   SC(call_global_inline, V8.CallGlobalInline)                         \
   SC(call_global_inline_miss, V8.CallGlobalInlineMiss)                \
   SC(constructed_objects, V8.ConstructedObjects)                      \
   SC(constructed_objects_runtime, V8.ConstructedObjectsRuntime)       \
   SC(constructed_objects_stub, V8.ConstructedObjectsStub)             \
   SC(negative_lookups, V8.NegativeLookups)                            \
   SC(negative_lookups_miss, V8.NegativeLookupsMiss)                   \
+  SC(megamorphic_stub_cache_probes, V8.MegamorphicStubCacheProbes)    \
+  SC(megamorphic_stub_cache_misses, V8.MegamorphicStubCacheMisses)    \
+  SC(megamorphic_stub_cache_updates, V8.MegamorphicStubCacheUpdates)  \
   SC(array_function_runtime, V8.ArrayFunctionRuntime)                 \
   SC(array_function_native, V8.ArrayFunctionNative)                   \
   SC(for_in, V8.ForIn)                                                \
   SC(enum_cache_hits, V8.EnumCacheHits)                               \
   SC(enum_cache_misses, V8.EnumCacheMisses)                           \
   SC(zone_segment_bytes, V8.ZoneSegmentBytes)                         \
   SC(compute_entry_frame, V8.ComputeEntryFrame)                       \
   SC(generic_binary_stub_calls, V8.GenericBinaryStubCalls)            \
   SC(generic_binary_stub_calls_regs, V8.GenericBinaryStubCallsRegs)   \
   SC(string_add_runtime, V8.StringAddRuntime)                         \
@@ skipping 90 matching lines @@
   // Sliding state window counters.
   StatsCounter state_counters_[kSlidingStateWindowCounterCount];
   friend class Isolate;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(Counters);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_V8_COUNTERS_H_