Let MetricsService know about some Android Activities

base/metrics/histogram_base.h

Index: base/metrics/histogram_base.h
diff --git a/base/metrics/histogram_base.h b/base/metrics/histogram_base.h
index 11b9a45b3831630f0841fb484988a111460d747b..566b4752f68ea0c35d2d85536ca5f2df22889250 100644
--- a/base/metrics/histogram_base.h
+++ b/base/metrics/histogram_base.h
@@ -58,6 +58,9 @@ class BASE_EXPORT HistogramBase {
     kNoFlags = 0,
     kUmaTargetedHistogramFlag = 0x1,  // Histogram should be UMA uploaded.
 
+    // Indicate that this is a stability histogram.
+    kStabilityHistogramFlag = 0x2,
+
     // Indicate that the histogram was pickled to be sent across an IPC Channel.
     // If we observe this flag on a histogram being aggregated into after IPC,
     // then we are running in a single process mode, and the aggregation should