Quantify initial stability report edge cases.

base/metrics/histogram_macros.h

Index: base/metrics/histogram_macros.h
diff --git a/base/metrics/histogram_macros.h b/base/metrics/histogram_macros.h
index dcde7255c8dafee8e28c09e21baf492408ea8682..1307257441f39ccbcafaf22ce41253e8cb045cbb 100644
--- a/base/metrics/histogram_macros.h
+++ b/base/metrics/histogram_macros.h
@@ -140,18 +140,25 @@
     LOCAL_HISTOGRAM_CUSTOM_COUNTS(name, sample, 1, 10000, 50)
 
 #define LOCAL_HISTOGRAM_CUSTOM_COUNTS(name, sample, min, max, bucket_count) \
-    STATIC_HISTOGRAM_POINTER_BLOCK(name, Add(sample), \
-        base::Histogram::FactoryGet(name, min, max, bucket_count, \
-                                    base::HistogramBase::kNoFlags))
+    INTERNAL_HISTOGRAM_CUSTOM_COUNTS_WITH_FLAG(                             \
+        name, sample, min, max, bucket_count, base::HistogramBase::kNoFlags)
+
+// This is a helper macro used by other macros and shouldn't be used directly.
+#define INTERNAL_HISTOGRAM_CUSTOM_COUNTS_WITH_FLAG(name, sample, min, max, \
+                                                   bucket_count, flag)     \
+    STATIC_HISTOGRAM_POINTER_BLOCK(                                        \
+        name, Add(sample),                                                 \
+        base::Histogram::FactoryGet(name, min, max, bucket_count, flag))
 
 // This is a helper macro used by other macros and shouldn't be used directly.
 // One additional bucket is created in the LinearHistogram for the illegal
 // values >= boundary_value so that mistakes in calling the UMA enumeration
 // macros can be detected.
-#define HISTOGRAM_ENUMERATION_WITH_FLAG(name, sample, boundary, flag) \
-    STATIC_HISTOGRAM_POINTER_BLOCK(name, Add(sample), \
-        base::LinearHistogram::FactoryGet(name, 1, boundary, boundary + 1, \
-            flag))
+#define INTERNAL_HISTOGRAM_ENUMERATION_WITH_FLAG(name, sample, boundary, flag) \
+    STATIC_HISTOGRAM_POINTER_BLOCK(                                            \
+        name, Add(sample),                                                     \
+        base::LinearHistogram::FactoryGet(                                     \
+            name, 1, boundary, boundary + 1, flag))
 
 #define LOCAL_HISTOGRAM_PERCENTAGE(name, under_one_hundred) \
     LOCAL_HISTOGRAM_ENUMERATION(name, under_one_hundred, 101)
@@ -229,9 +236,18 @@
     name, sample, 1, 10000, 50)
 
 #define UMA_HISTOGRAM_CUSTOM_COUNTS(name, sample, min, max, bucket_count) \
-    STATIC_HISTOGRAM_POINTER_BLOCK(name, Add(sample), \
-        base::Histogram::FactoryGet(name, min, max, bucket_count, \
-            base::HistogramBase::kUmaTargetedHistogramFlag))
+    INTERNAL_HISTOGRAM_CUSTOM_COUNTS_WITH_FLAG(                           \
+        name, sample, min, max, bucket_count,                             \
+        base::HistogramBase::kUmaTargetedHistogramFlag)
+
+#define UMA_STABILITY_HISTOGRAM_COUNTS_100(name, sample) \
+    UMA_STABILITY_HISTOGRAM_CUSTOM_COUNTS(name, sample, 1, 100, 50)
+
+#define UMA_STABILITY_HISTOGRAM_CUSTOM_COUNTS(name, sample, min, max, \
+                                              bucket_count)           \
+    INTERNAL_HISTOGRAM_CUSTOM_COUNTS_WITH_FLAG(                       \
+        name, sample, min, max, bucket_count,                         \
+        base::HistogramBase::kUmaStabilityHistogramFlag)
 
 #define UMA_HISTOGRAM_MEMORY_KB(name, sample) UMA_HISTOGRAM_CUSTOM_COUNTS( \
     name, sample, 1000, 500000, 50)
@@ -253,14 +269,16 @@
 // The samples should always be strictly less than |boundary_value|.  For more
 // details, see the comment for the |LOCAL_HISTOGRAM_ENUMERATION| macro, above.
 #define UMA_HISTOGRAM_ENUMERATION(name, sample, boundary_value) \
-    HISTOGRAM_ENUMERATION_WITH_FLAG(name, sample, boundary_value, \
+    INTERNAL_HISTOGRAM_ENUMERATION_WITH_FLAG(                   \
+        name, sample, boundary_value,                           \
         base::HistogramBase::kUmaTargetedHistogramFlag)
 
 // Similar to UMA_HISTOGRAM_ENUMERATION, but used for recording stability
 // histograms.  Use this if recording a histogram that should be part of the
 // initial stability log.
 #define UMA_STABILITY_HISTOGRAM_ENUMERATION(name, sample, boundary_value) \
-    HISTOGRAM_ENUMERATION_WITH_FLAG(name, sample, boundary_value, \
+    INTERNAL_HISTOGRAM_ENUMERATION_WITH_FLAG(                             \
+        name, sample, boundary_value,                                     \
         base::HistogramBase::kUmaStabilityHistogramFlag)
 
 #define UMA_HISTOGRAM_CUSTOM_ENUMERATION(name, sample, custom_ranges) \