Add histograms for idle notification and incremental marking steps

src/counters.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_COUNTERS_H_
 #define V8_COUNTERS_H_
 
 #include "include/v8.h"
 #include "src/allocation.h"
 #include "src/base/platform/elapsed-timer.h"
@@ skipping 274 matching lines @@
   }
 
  private:
   HistogramTimer* timer_;
 #ifdef DEBUG
   bool skipped_timer_start_;
 #endif
 };
 
 
-#define HISTOGRAM_TIMER_LIST(HT)                                      \
-  /* Garbage collection timers. */                                    \
-  HT(gc_compactor, V8.GCCompactor)                                    \
-  HT(gc_scavenger, V8.GCScavenger)                                    \
-  HT(gc_context, V8.GCContext) /* GC context cleanup time */          \
-  /* Parsing timers. */                                               \
-  HT(parse, V8.Parse)                                                 \
-  HT(parse_lazy, V8.ParseLazy)                                        \
-  HT(pre_parse, V8.PreParse)                                          \
-  /* Total compilation times. */                                      \
-  HT(compile, V8.Compile)                                             \
-  HT(compile_eval, V8.CompileEval)                                    \
+#define HISTOGRAM_TIMER_LIST(HT)                             \
+  /* Garbage collection timers. */                           \
+  HT(gc_compactor, V8.GCCompactor)                           \
+  HT(gc_scavenger, V8.GCScavenger)                           \
+  HT(gc_context, V8.GCContext) /* GC context cleanup time */ \
+  HT(gc_idle_notification, V8.GCIdleNotification)            \
+  HT(gc_incremental_marking, V8.GCIncrementalMarking)        \
+  /* Parsing timers. */                                      \
+  HT(parse, V8.Parse)                                        \
+  HT(parse_lazy, V8.ParseLazy)                               \
+  HT(pre_parse, V8.PreParse)                                 \
+  /* Total compilation times. */                             \
+  HT(compile, V8.Compile)                                    \
+  HT(compile_eval, V8.CompileEval)                           \
   HT(compile_lazy, V8.CompileLazy)
 
 #define HISTOGRAM_PERCENTAGE_LIST(HP)                                 \
   /* Heap fragmentation. */                                           \
   HP(external_fragmentation_total,                                    \
      V8.MemoryExternalFragmentationTotal)                             \
   HP(external_fragmentation_old_pointer_space,                        \
      V8.MemoryExternalFragmentationOldPointerSpace)                   \
   HP(external_fragmentation_old_data_space,                           \
      V8.MemoryExternalFragmentationOldDataSpace)                      \
@@ skipping 367 matching lines @@
   friend class Isolate;
 
   explicit Counters(Isolate* isolate);
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(Counters);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_COUNTERS_H_