Add histograms to track fraction of heap spaces and percentage of crankshaft code.

src/heap.h

Index: src/heap.h
diff --git a/src/heap.h b/src/heap.h
index f5b99d6e53dd28d794baac7b99807eeb90d8fb08..575f06f5d748ff6746a55b02c20c2edee24b9cf8 100644
--- a/src/heap.h
+++ b/src/heap.h
@@ -1660,6 +1660,14 @@ class Heap {
     total_regexp_code_generated_ += size;
   }
 
+  void IncrementCodeGeneratedBytes(bool is_crankshafted, int size) {
+    if (is_crankshafted) {
+      crankshaft_codegen_bytes_generated_ += size;
+    } else {
+      full_codegen_bytes_generated_ += size;
+    }
+  }
+
   // Returns maximum GC pause.
   double get_max_gc_pause() { return max_gc_pause_; }
 
@@ -2355,6 +2363,10 @@ class Heap {
   unsigned int gc_count_at_last_idle_gc_;
   int scavenges_since_last_idle_round_;
 
+  // These two counters are monotomically increasing and never reset.
+  size_t full_codegen_bytes_generated_;
+  size_t crankshaft_codegen_bytes_generated_;
+
   // If the --deopt_every_n_garbage_collections flag is set to a positive value,
   // this variable holds the number of garbage collections since the last
   // deoptimization triggered by garbage collection.