Refactor metrics_utils from select_to_speak.

This moves all metrics related functionality into a separate class,
and is a pure refactor.

Cq-Include-Trybots: luci.chromium.try:closure_compilation
Change-Id: Idba2a55655c3e67476500618e6c324a10cfa0b37
Reviewed-on: https://chromium-review.googlesource.com/1141115Reviewed-by: David Tseng <dtseng@chromium.org>
Commit-Queue: Katie Dektar <katie@chromium.org>
Cr-Commit-Position: refs/heads/master@{#576319}

chrome/browser/resources/chromeos/select_to_speak/BUILD.gn

@@ -35,6 +35,7 @@ run_jsbundler("select_to_speak_copied_files") {
     "closure_shim.js",
     "earcons/null_selection.ogg",
     "input_handler.js",
+    "metrics_utils.js",
     "node_utils.js",
     "options.css",
     "options.html",
@@ -171,6 +172,7 @@ js_type_check("closure_compile") {
     ":../chromevox/cvox2/background/tree_walker",
     ":closure_shim",
     ":input_handler",
+    ":metrics_utils",
     ":node_utils",
     ":paragraph_utils",
     ":rect_utils",
@@ -185,6 +187,7 @@ js_library("select_to_speak") {
     ":../chromevox/cvox2/background/automation_util",
     ":../chromevox/cvox2/background/constants",
     ":input_handler",
+    ":metrics_utils",
     ":node_utils",
     ":paragraph_utils",
     ":rect_utils",
@@ -196,7 +199,6 @@ js_library("select_to_speak") {
     "$externs_path/chrome_extensions.js",
     "$externs_path/clipboard.js",
     "$externs_path/command_line_private.js",
-    "$externs_path/metrics_private.js",
     "externs.js",
   ]
 }
@@ -250,6 +252,10 @@ js_library("input_handler") {
 js_library("rect_utils") {
 }
 
+js_library("metrics_utils") {
+  externs_list = [ "$externs_path/metrics_private.js" ]
+}
+
 js_library("../chromevox/cvox2/background/automation_util") {
   deps = [
     ":../chromevox/cvox2/background/automation_predicate",

chrome/browser/resources/chromeos/select_to_speak/manifest.json.jinja2

@@ -17,6 +17,7 @@
       "tree_walker.js",
       "automation_util.js",
       "input_handler.js",
+      "metrics_utils.js",
       "node_utils.js",
       "paragraph_utils.js",
       "word_utils.js",

chrome/browser/resources/chromeos/select_to_speak/metrics_utils.js

+// Copyright 2018 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Utilities for UMA metrics.
+
+/**
+ * @constructor
+ */
+let MetricsUtils = function() {};
+
+/**
+ * Defines an enumeration metric. The |EVENT_COUNT| must be kept in sync
+ * with the number of enum values for each metric in
+ * tools/metrics/histograms/enums.xml.
+ * @typedef {{EVENT_COUNT: number, METRIC_NAME: string}}
+ */
+MetricsUtils.EnumerationMetric;
+
+/**
+ * CrosSelectToSpeakStartSpeechMethod enums.
+ * These values are persisted to logs and should not be renumbered or re-used.
+ * See tools/metrics/histograms/enums.xml.
+ * @enum {number}
+ */
+MetricsUtils.StartSpeechMethod = {
+  MOUSE: 0,
+  KEYSTROKE: 1,
+};
+
+/**
+ * Constants for the start speech method metric,
+ * CrosSelectToSpeakStartSpeechMethod.
+ * @type {MetricsUtils.EnumerationMetric}
+ */
+MetricsUtils.START_SPEECH_METHOD_METRIC = {
+  EVENT_COUNT: Object.keys(MetricsUtils.StartSpeechMethod).length,
+  METRIC_NAME: 'Accessibility.CrosSelectToSpeak.StartSpeechMethod'
+};
+
+/**
+ * CrosSelectToSpeakStateChangeEvent enums.
+ * These values are persisted to logs and should not be renumbered or re-used.
+ * See tools/metrics/histograms/enums.xml.
+ * @enum {number}
+ */
+MetricsUtils.StateChangeEvent = {
+  START_SELECTION: 0,
+  CANCEL_SPEECH: 1,
+  CANCEL_SELECTION: 2,
+};
+
+/**
+ * Constants for the state change metric, CrosSelectToSpeakStateChangeEvent.
+ * @type {MetricsUtils.EnumerationMetric}
+ */
+MetricsUtils.STATE_CHANGE_METRIC = {
+  EVENT_COUNT: Object.keys(MetricsUtils.StateChangeEvent).length,
+  METRIC_NAME: 'Accessibility.CrosSelectToSpeak.StateChangeEvent'
+};
+
+/**
+ * The start speech metric name.
+ * @type {string}
+ */
+MetricsUtils.START_SPEECH_METRIC =
+    'Accessibility.CrosSelectToSpeak.StartSpeech';
+
+/**
+ * The cancel speech metric name.
+ * @type {string}
+ */
+MetricsUtils.CANCEL_SPEECH_METRIC =
+    'Accessibility.CrosSelectToSpeak.CancelSpeech';
+
+/**
+ * The speech pitch histogram metric name.
+ * @type {string}
+ */
+MetricsUtils.SPEECH_PITCH_METRIC =
+    'Accessibility.CrosSelectToSpeak.SpeechPitch';
+
+/**
+ * The speech rate histogram metric name.
+ * @type {string}
+ */
+MetricsUtils.SPEECH_RATE_METRIC = 'Accessibility.CrosSelectToSpeak.SpeechRate';
+
+/**
+ * The word highlighting metric name.
+ * @type {string}
+ */
+MetricsUtils.WORD_HIGHLIGHTING_METRIC =
+    'Accessibility.CrosSelectToSpeak.WordHighlighting';
+
+
+/**
+ * Records a cancel event if speech was in progress.
+ * @param {boolean} speaking Whether speech was in progress
+ * @public
+ */
+MetricsUtils.recordCancelIfSpeaking = function(speaking) {
+  if (speaking) {
+    MetricsUtils.recordCancelEvent_();
+  }
+};
+
+/**
+ * Converts the speech rate into an enum based on
+ * tools/metrics/histograms/enums.xml.
+ * These values are persisted to logs. Entries should not be
+ * renumbered and numeric values should never be reused.
+ * @param {number} speechRate The current speech rate.
+ * @return {number} The current speech rate as an int for metrics.
+ * @private
+ */
+MetricsUtils.speechRateToSparceHistogramInt_ = function(speechRate) {
+  return speechRate * 100;
+};
+
+/**
+ * Converts the speech pitch into an enum based on
+ * tools/metrics/histograms/enums.xml.
+ * These values are persisted to logs. Entries should not be
+ * renumbered and numeric values should never be reused.
+ * @param {number} speechPitch The current speech pitch.
+ * @return {number} The current speech pitch as an int for metrics.
+ * @private
+ */
+MetricsUtils.speechPitchToSparceHistogramInt_ = function(speechPitch) {
+  return speechPitch * 100;
+};
+
+/**
+ * Records an event that Select-to-Speak has begun speaking.
+ * @param {number} method The CrosSelectToSpeakStartSpeechMethod enum
+ *    that reflects how this event was triggered by the user.
+ * @param {number} speechRate The current speech rate.
+ * @param {number} speechPitch The current speech pitch.
+ * @param {boolean} wordHighlightingEnabled If word highlighting is enabled.
+ * @public
+ */
+MetricsUtils.recordStartEvent = function(
+    method, speechRate, speechPitch, wordHighlightingEnabled) {
+  chrome.metricsPrivate.recordUserAction(MetricsUtils.START_SPEECH_METRIC);
+  chrome.metricsPrivate.recordSparseValue(
+      MetricsUtils.SPEECH_RATE_METRIC,
+      MetricsUtils.speechRateToSparceHistogramInt_(speechRate));
+  chrome.metricsPrivate.recordSparseValue(
+      MetricsUtils.SPEECH_PITCH_METRIC,
+      MetricsUtils.speechPitchToSparceHistogramInt_(speechPitch));
+  chrome.metricsPrivate.recordBoolean(
+      MetricsUtils.WORD_HIGHLIGHTING_METRIC, wordHighlightingEnabled);
+  chrome.metricsPrivate.recordEnumerationValue(
+      MetricsUtils.START_SPEECH_METHOD_METRIC.METRIC_NAME, method,
+      MetricsUtils.START_SPEECH_METHOD_METRIC.EVENT_COUNT);
+};
+
+/**
+ * Records an event that Select-to-Speak speech has been canceled.
+ * @private
+ */
+MetricsUtils.recordCancelEvent_ = function() {
+  chrome.metricsPrivate.recordUserAction(MetricsUtils.CANCEL_SPEECH_METRIC);
+};
+
+/**
+ * Records a user-requested state change event from a given state.
+ * @param {number} changeType
+ * @public
+ */
+MetricsUtils.recordSelectToSpeakStateChangeEvent = function(changeType) {
+  chrome.metricsPrivate.recordEnumerationValue(
+      MetricsUtils.STATE_CHANGE_METRIC.METRIC_NAME, changeType,
+      MetricsUtils.STATE_CHANGE_METRIC.EVENT_COUNT);
+};

chrome/browser/resources/chromeos/select_to_speak/select_to_speak.js

@@ -6,50 +6,6 @@ var AutomationEvent = chrome.automation.AutomationEvent;
 var EventType = chrome.automation.EventType;
 var RoleType = chrome.automation.RoleType;
 
-/**
- * CrosSelectToSpeakStartSpeechMethod enums.
- * These values are persisted to logs and should not be renumbered or re-used.
- * See tools/metrics/histograms/enums.xml.
- * @enum {number}
- */
-const StartSpeechMethod = {
-  MOUSE: 0,
-  KEYSTROKE: 1,
-};
-
-/**
- * The number of enum values in CrosSelectToSpeakStartSpeechMethod. This should
- * be kept in sync with the enum count in tools/metrics/histograms/enums.xml.
- * @type {number}
- */
-const START_SPEECH_METHOD_COUNT = Object.keys(StartSpeechMethod).length;
-
-/**
- * CrosSelectToSpeakStateChangeEvent enums.
- * These values are persisted to logs and should not be renumbered or re-used.
- * See tools/metrics/histograms/enums.xml.
- * @enum {number}
- */
-const StateChangeEvent = {
-  START_SELECTION: 0,
-  CANCEL_SPEECH: 1,
-  CANCEL_SELECTION: 2,
-};
-
-/**
- * The number of enum values in CrosSelectToSpeakStateChangeEvent. This should
- * be kept in sync with the enum count in tools/metrics/histograms/enums.xml.
- * @type {number}
- */
-const STATE_CHANGE_EVENT_COUNT = Object.keys(StateChangeEvent).length;
-
-/**
- * The name of the state change request metric.
- * @type {string}
- */
-const STATE_CHANGE_EVENT_METRIC_NAME =
-    'Accessibility.CrosSelectToSpeak.StateChangeEvent';
-
 // This must be the same as in ash/system/accessibility/select_to_speak_tray.cc:
 // ash::kSelectToSpeakTrayClassName.
 const SELECT_TO_SPEAK_TRAY_CLASS_NAME =
@@ -237,7 +193,9 @@ SelectToSpeak.prototype = {
         return;
       }
       this.startSpeechQueue_(nodes);
-      this.recordStartEvent_(StartSpeechMethod.MOUSE);
+      MetricsUtils.recordStartEvent(
+          MetricsUtils.StartSpeechMethod.MOUSE, this.speechRate_,
+          this.speechPitch_, this.wordHighlight_);
     }.bind(this));
   },
 
@@ -391,7 +349,9 @@ SelectToSpeak.prototype = {
       return;
     }
     this.initializeScrollingToOffscreenNodes_(focusedNode.root);
-    this.recordStartEvent_(StartSpeechMethod.KEYSTROKE);
+    MetricsUtils.recordStartEvent(
+        MetricsUtils.StartSpeechMethod.KEYSTROKE, this.speechRate_,
+        this.speechPitch_, this.wordHighlight_);
   },
 
   /**
@@ -527,21 +487,21 @@ SelectToSpeak.prototype = {
         // Start selection.
         this.inputHandler_.setTrackingMouse(true);
         this.onStateChanged_(SelectToSpeakState.SELECTING);
-        this.recordSelectToSpeakStateChangeEvent_(
-            StateChangeEvent.START_SELECTION);
+        MetricsUtils.recordSelectToSpeakStateChangeEvent(
+            MetricsUtils.StateChangeEvent.START_SELECTION);
         break;
       case SelectToSpeakState.SPEAKING:
         // Stop speaking.
         this.cancelIfSpeaking_(true /* clear the focus ring */);
-        this.recordSelectToSpeakStateChangeEvent_(
-            StateChangeEvent.CANCEL_SPEECH);
+        MetricsUtils.recordSelectToSpeakStateChangeEvent(
+            MetricsUtils.StateChangeEvent.CANCEL_SPEECH);
         break;
       case SelectToSpeakState.SELECTING:
         // Cancelled selection.
         this.inputHandler_.setTrackingMouse(false);
         this.onStateChanged_(SelectToSpeakState.INACTIVE);
-        this.recordSelectToSpeakStateChangeEvent_(
-            StateChangeEvent.CANCEL_SELECTION);
+        MetricsUtils.recordSelectToSpeakStateChangeEvent(
+            MetricsUtils.StateChangeEvent.CANCEL_SELECTION);
     }
     this.onStateChangeRequestedCallbackForTest_ &&
         this.onStateChangeRequestedCallbackForTest_();
@@ -769,7 +729,7 @@ SelectToSpeak.prototype = {
    *    as well.
    */
   cancelIfSpeaking_: function(clearFocusRing) {
-    chrome.tts.isSpeaking(this.recordCancelIfSpeaking_.bind(this));
+    chrome.tts.isSpeaking(MetricsUtils.recordCancelIfSpeaking);
     if (clearFocusRing) {
       this.stopAll_();
     } else {
@@ -778,77 +738,6 @@ SelectToSpeak.prototype = {
     }
   },
 
-  /**
-   * Records a cancel event if speech was in progress.
-   * @param {boolean} speaking Whether speech was in progress
-   */
-  recordCancelIfSpeaking_: function(speaking) {
-    if (speaking) {
-      this.recordCancelEvent_();
-    }
-  },
-
-  /**
-   * Converts the speech rate into an enum based on
-   * tools/metrics/histograms/enums.xml.
-   * These values are persisted to logs. Entries should not be
-   * renumbered and numeric values should never be reused.
-   * @return {number} the current speech rate as an int for metrics.
-   */
-  speechRateToSparceHistogramInt_: function() {
-    return this.speechRate_ * 100;
-  },
-
-  /**
-   * Converts the speech pitch into an enum based on
-   * tools/metrics/histograms/enums.xml.
-   * These values are persisted to logs. Entries should not be
-   * renumbered and numeric values should never be reused.
-   * @return {number} the current speech pitch as an int for metrics.
-   */
-  speechPitchToSparceHistogramInt_: function() {
-    return this.speechPitch_ * 100;
-  },
-
-  /**
-   * Records an event that Select-to-Speak has begun speaking.
-   * @param {number} method The CrosSelectToSpeakStartSpeechMethod enum
-   *    that reflects how this event was triggered by the user.
-   */
-  recordStartEvent_: function(method) {
-    chrome.metricsPrivate.recordUserAction(
-        'Accessibility.CrosSelectToSpeak.StartSpeech');
-    chrome.metricsPrivate.recordSparseValue(
-        'Accessibility.CrosSelectToSpeak.SpeechRate',
-        this.speechRateToSparceHistogramInt_());
-    chrome.metricsPrivate.recordSparseValue(
-        'Accessibility.CrosSelectToSpeak.SpeechPitch',
-        this.speechPitchToSparceHistogramInt_());
-    chrome.metricsPrivate.recordBoolean(
-        'Accessibility.CrosSelectToSpeak.WordHighlighting',
-        this.wordHighlight_);
-    chrome.metricsPrivate.recordEnumerationValue(
-        'Accessibility.CrosSelectToSpeak.StartSpeechMethod', method,
-        START_SPEECH_METHOD_COUNT);
-  },
-
-  /**
-   * Records an event that Select-to-Speak speech has been canceled.
-   */
-  recordCancelEvent_: function() {
-    chrome.metricsPrivate.recordUserAction(
-        'Accessibility.CrosSelectToSpeak.CancelSpeech');
-  },
-
-  /**
-   * Records a user-requested state change event from a given state.
-   * @param {number} changeType
-   */
-  recordSelectToSpeakStateChangeEvent_: function(changeType) {
-    chrome.metricsPrivate.recordEnumerationValue(
-        STATE_CHANGE_EVENT_METRIC_NAME, changeType, STATE_CHANGE_EVENT_COUNT);
-  },
-
   /**
    * Loads preferences from chrome.storage, sets default values if
    * necessary, and registers a listener to update prefs when they