Bug 1935420 - Migrate histograms to use Glean APIs for A11Y_*, r=chutten.

Differential Revision: https://phabricator.services.mozilla.com/D235342

accessible/base/NotificationController.cpp

@@ -21,7 +21,7 @@
 #include "mozilla/PresShell.h"
 #include "mozilla/ProfilerMarkers.h"
 #include "nsAccessibilityService.h"
-#include "mozilla/Telemetry.h"
+#include "mozilla/glean/AccessibleMetrics.h"
 
 using namespace mozilla;
 using namespace mozilla::a11y;
@@ -679,7 +679,7 @@ void NotificationController::ProcessMutationEvents() {
 void NotificationController::WillRefresh(mozilla::TimeStamp aTime) {
   AUTO_PROFILER_MARKER_TEXT("NotificationController::WillRefresh", A11Y, {},
                             ""_ns);
-  Telemetry::AutoTimer<Telemetry::A11Y_TREE_UPDATE_TIMING_MS> timer;
+  auto timer = glean::a11y::tree_update_timing.Measure();
   // DO NOT ADD CODE ABOVE THIS BLOCK: THIS CODE IS MEASURING TIMINGS.
 
   AUTO_PROFILER_LABEL("NotificationController::WillRefresh", A11Y);

accessible/base/Statistics.h

@@ -7,14 +7,14 @@
 #ifndef A11Y_STATISTICS_H_
 #define A11Y_STATISTICS_H_
 
-#include "mozilla/Telemetry.h"
+#include "mozilla/glean/AccessibleMetrics.h"
 
 namespace mozilla {
 namespace a11y {
 namespace statistics {
 
 inline void A11yConsumers(uint32_t aConsumer) {
-  Telemetry::Accumulate(Telemetry::A11Y_CONSUMERS, aConsumer);
+  glean::a11y::consumers.AccumulateSingleSample(aConsumer);
 }
 
 }  // namespace statistics

accessible/metrics.yaml

@@ -154,3 +154,41 @@ a11y:
       - always
       - never
     telemetry_mirror: A11Y_THEME
+
+  consumers:
+    type: custom_distribution
+    description: |
+      A list of known accessibility clients that inject into Firefox process space (see https://searchfox.org/mozilla-central/source/accessible/windows/msaa/Compatibility.h).
+      This metric was generated to correspond to the Legacy Telemetry enumerated histogram A11Y_CONSUMERS.
+    range_min: 0
+    range_max: 11
+    bucket_count: 12
+    histogram_type: linear
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1382820
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1462238
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1382820
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1462238
+    notification_emails:
+      - accessibility@mozilla.com
+      - jteh@mozilla.com
+    expires: never
+    telemetry_mirror: A11Y_CONSUMERS
+
+  tree_update_timing:
+    type: timing_distribution
+    description: >
+      The amount of time taken to update the accessibility tree (ms)
+
+      This metric was generated to correspond to the Legacy Telemetry
+      exponential histogram A11Y_TREE_UPDATE_TIMING_MS.
+    time_unit: millisecond
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1424768
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1424768
+    notification_emails:
+      - asurkov@mozilla.com
+    expires: never
+    telemetry_mirror: A11Y_TREE_UPDATE_TIMING_MS