Don't report array buffer allocations less than 1 Mb.

src/counters.h

Index: src/counters.h
diff --git a/src/counters.h b/src/counters.h
index 79fd2359a783e49f503e7e11193329b6ea2b8eb6..4094e001fcd550e8ff170e96440472b0edf6fb6d 100644
--- a/src/counters.h
+++ b/src/counters.h
@@ -935,7 +935,7 @@ class RuntimeCallTimerScope {
      51)                                                                      \
   HR(wasm_functions_per_wasm_module, V8.WasmFunctionsPerModule.wasm, 1,       \
      100000, 51)                                                              \
-  HR(array_buffer_big_allocations, V8.ArrayBufferBigAllocations, 0, 4096, 13) \
+  HR(array_buffer_big_allocations, V8.ArrayBufferBigAllocations, 1, 4096, 13) \

[Ilya Sherman, 2017/05/01 19:51:14]

Please rename the histogram, as you are changing the bucket layout for it. 
Otherwise, you'll get data mixed in from multiple versions, and the blended data
will look rather confusing.

[kschimpf, 2017/05/04 20:51:36]

Is this really necessary. This metric was created very recently and isn't really
being used anywhere (yet).

Otherwise, I'd be more willing to change this back to starting at zero.

[Ilya Sherman, 2017/05/04 21:21:21]

Well, I think it might actually be the same bucket layout regardless of whether
the first value is 0 or 1 -- I think the code will automatically correct a 0 to
a 1, and reserve the zero-th bucket as an underflow bucket.  I'd strongly
encourage you to double-check me on this, as I'm not familiar with what exactly
these V8 wrappers are doing under the hood.  If the actual bucket layout is
changing, then you should definitely either (a) restore the previous layout, or
(b) rename the histogram.

However, you're still blending data with rather different distributions across
multiple versions.  The best practice would be to rename the histogram.  The
next-best option would be to document the change in semantics in the
histograms.xml description... though such documentation is very easy for readers
to miss.

What is your concern w.r.t. renaming the histogram?  

[kschimpf, 2017/05/05 17:05:37]

Ok. Changing the name of the metric, and introducing it into V8.

   HR(array_buffer_new_size_failures, V8.ArrayBufferNewSizeFailures, 0, 4096, 13)
 
 #define HISTOGRAM_TIMER_LIST(HT)                                               \