Let MetricsService know about some Android Activities

To tune our crash states more finely, we need to track which Activity is in the
foreground when Chrome is killed. Add piping to let MetricsService know when
Activities are swapped in and out by the user.

The CL makes MetricsService track how many times particular Activities have been
launched, as well as how often Chrome was improperly closed while one of these
Activities was in the foreground (i.e. crashed). These numbers are concatenated
into a histogram, which is then sent to the server.

BUG=321346

Review URL: https://codereview.chromium.org/137623002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@250410 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 15 insertions, 3 deletions

diff --git a/base/metrics/histogram.h b/base/metrics/histogram.h
index 9845362..7a6c688 100644
--- a/base/metrics/histogram.h
+++ b/base/metrics/histogram.h
@@ -190,6 +190,12 @@ class Lock;
         base::Histogram::FactoryGet(name, min, max, bucket_count, \
                                     base::HistogramBase::kNoFlags))
 
+// This is a helper macro used by other macros and shouldn't be used directly.
+#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 HISTOGRAM_PERCENTAGE(name, under_one_hundred) \
     HISTOGRAM_ENUMERATION(name, under_one_hundred, 101)
 
@@ -349,9 +355,15 @@ class Lock;
 // The samples should always be strictly less than |boundary_value|.  For more
 // details, see the comment for the |HISTOGRAM_ENUMERATION| macro, above.
 #define UMA_HISTOGRAM_ENUMERATION(name, sample, boundary_value) \
-    STATIC_HISTOGRAM_POINTER_BLOCK(name, Add(sample), \
-        base::LinearHistogram::FactoryGet(name, 1, boundary_value, \
-            boundary_value + 1, base::HistogramBase::kUmaTargetedHistogramFlag))
+    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, \
+        base::HistogramBase::kUmaStabilityHistogramFlag)
 
 #define UMA_HISTOGRAM_CUSTOM_ENUMERATION(name, sample, custom_ranges) \
     STATIC_HISTOGRAM_POINTER_BLOCK(name, Add(sample), \