Fix degraded typing feedback

- EditableTextBase's state transitions that detect insertions are unreliable:
1. when typing quickly, Chrome can and does combine events. type the keys 1, 2,
3 quickly and you might get value/text changes for "1", "12", and "123"; or you
might get value changes for "1", "123". The latter is really bad and triggers
the insertion (with length > 1) state erroniously.
2. the source of the insertion is unclear. It might have been from a paste, programmatic splicing.
3. It is impossible to reconstruct what part of the text actually got
inserted. Trivial example: 'aaa', 'aaaaaaaa'. Unknown whether the entire value was replaced, or just a substring.

In this change, we will turn off insertion announcements, which were being
triggered in many undesirable code paths.

Instead, we will:
- listen to clipboard events for cut, copy, paste (and
remove the previous copy command)
- fixes the regression introduced by splitting
text field into several subroles. Set selection wasn't working.

Test: type a lot with various typing echo settings and cut/copy/paste.

Bug: 791157
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: Ida442aa0656c1d66e489c6064f8959ccb7177b46
Reviewed-on: https://chromium-review.googlesource.com/804535
Commit-Queue: David Tseng <dtseng@chromium.org>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#521793}

chrome/browser/resources/chromeos/chromevox/chromevox/background/keymaps/next_keymap.json

@@ -752,15 +752,6 @@
         }
       }
     },
-    {
-      "command": "copy",
-      "sequence": {
-        "keys": {
-          "keyCode": [67],
-          "ctrlKey": [true]
-        }
-      }
-    },
     {
       "command": "previousRow",
       "sequence": {

chrome/browser/resources/chromeos/chromevox/chromevox/injected/event_watcher_test.unitjs

@@ -404,6 +404,7 @@ TEST_F('CvoxEventWatcherUnitTest', 'EditableTextListbox', function() {
  */
 TEST_F('CvoxEventWatcherUnitTest', 'EditableTextListboxUpdatingInput',
     function() {
+  cvox.ChromeVoxEditableTextBase.shouldSpeakInsertions = true;
   this.loadHtml('<div>' +
       '<button id="before">Before</button>' +
       '<label for="input">Query</label>' +

chrome/browser/resources/chromeos/chromevox/common/editable_text_base.js

@@ -194,6 +194,13 @@ cvox.ChromeVoxEditableTextBase.useIBeamCursor = cvox.ChromeVox.isMac;
 cvox.ChromeVoxEditableTextBase.eventTypingEcho = false;
 
 
+/**
+ * @type {boolean} Whether insertions (i.e. changes of greater than one
+ * character) should be spoken.
+ */
+cvox.ChromeVoxEditableTextBase.shouldSpeakInsertions = false;
+
+
 /**
  * The maximum number of characters that are short enough to speak in response
  * to an event. For example, if the user selects "Hello", we will speak
@@ -619,6 +626,8 @@ cvox.ChromeVoxEditableTextBase.prototype.describeTextChangedHelper = function(
   var triggeredByUser = evt.triggeredByUser;
 
   if (insertedLen > 1) {
+    if (!cvox.ChromeVoxEditableTextBase.shouldSpeakInsertions)
+      return;
     utterance = inserted;
   } else if (insertedLen == 1) {
     if ((cvox.ChromeVox.typingEcho == cvox.TypingEcho.WORD ||

chrome/browser/resources/chromeos/chromevox/common/editable_text_test.unitjs

@@ -111,6 +111,7 @@ CvoxEditableTextUnitTest.prototype = {
     cvox.ChromeVoxEditableTextBase.useIBeamCursor = true;
     cvox.ChromeVox.typingEcho = cvox.TypingEcho.CHARACTER_AND_WORD;
     cvox.ChromeVoxEditableTextBase.eventTypingEcho = false;
+    cvox.ChromeVoxEditableTextBase.shouldSpeakInsertions = true;
     cvox.ChromeVox.braille = new TestBraille();
 
     /** Simple mock. */

chrome/browser/resources/chromeos/chromevox/cvox2/background/background.js

@@ -159,6 +159,13 @@ Background = function() {
   chrome.accessibilityPrivate.onAccessibilityGesture.addListener(
       this.onAccessibilityGesture_);
 
+  document.addEventListener('copy', this.onClipboardEvent_);
+  document.addEventListener('cut', this.onClipboardEvent_);
+  document.addEventListener('paste', this.onClipboardEvent_);
+
+  /** @private {boolean} */
+  this.preventPasteOutput_ = false;
+
   /**
    * Maps a non-desktop root automation node to a range position suitable for
    *     restoration.
@@ -734,6 +741,42 @@ Background.prototype = {
     return true;
   },
 
+  /**
+   * Detects various clipboard events and provides spoken output.
+   *
+   * Note that paste is explicitly skipped sometimes because during a copy or
+   * cut, the copied or cut text is retrieved by pasting into a fake text
+   * area. To prevent this from triggering paste output, this staste is tracked
+   * via a field.
+   * @param {!Event} evt
+   * @private
+   */
+  onClipboardEvent_: function(evt) {
+    var text = '';
+    if (evt.type == 'paste') {
+      if (this.preventPasteOutput_) {
+        this.preventPasteOutput_ = false;
+        return;
+      }
+      text = evt.clipboardData.getData('text');
+      cvox.ChromeVox.tts.speak(
+          Msgs.getMsg(evt.type, [text]), cvox.QueueMode.QUEUE);
+    } else if (evt.type == 'copy' || evt.type == 'cut') {
+      window.setTimeout(function() {
+        this.preventPasteOutput_ = true;
+        var textarea = document.createElement('textarea');
+        document.body.appendChild(textarea);
+        textarea.focus();
+        document.execCommand('paste');
+        var clipboardContent = textarea.value;
+        textarea.remove();
+        cvox.ChromeVox.tts.speak(
+            Msgs.getMsg(evt.type, [clipboardContent]), cvox.QueueMode.FLUSH);
+        ChromeVoxState.instance.pageSel_ = null;
+      }.bind(this), 20);
+    }
+  },
+
   /** @private */
   setCurrentRangeToFocus_: function() {
     chrome.automation.getFocus(function(focus) {

chrome/browser/resources/chromeos/chromevox/cvox2/background/command_handler.js

@@ -576,19 +576,6 @@ CommandHandler.onCommand = function(command) {
       var target = ChromeVoxState.instance.currentRange_.start.node.root;
       output.withString(target.docUrl || '').go();
       return false;
-    case 'copy':
-      window.setTimeout(function() {
-        var textarea = document.createElement('textarea');
-        document.body.appendChild(textarea);
-        textarea.focus();
-        document.execCommand('paste');
-        var clipboardContent = textarea.value;
-        textarea.remove();
-        cvox.ChromeVox.tts.speak(
-            Msgs.getMsg('copy', [clipboardContent]), cvox.QueueMode.FLUSH);
-        ChromeVoxState.instance.pageSel_ = null;
-      }, 20);
-      return true;
     case 'toggleSelection':
       if (!ChromeVoxState.instance.pageSel_) {
         ChromeVoxState.instance.pageSel_ = ChromeVoxState.instance.currentRange;

chrome/browser/resources/chromeos/chromevox/cvox2/background/desktop_automation_handler.js

@@ -440,10 +440,13 @@ DesktopAutomationHandler.prototype = {
    * @param {!AutomationEvent} evt
    */
   onValueChanged: function(evt) {
-    // Delegate to the edit text handler if this is an editable but not richly
-    // editable which gets handled in text and text selection changed events.
-    if (evt.target.state[StateType.EDITABLE] &&
-        !evt.target.state[StateType.RICHLY_EDITABLE]) {
+    // Skip all unfocused text fields.
+    if (!evt.target.state[StateType.FOCUSED] &&
+        evt.target.state[StateType.EDITABLE])
+      return;
+
+    // Delegate to the edit text handler if this is an editable.
+    if (evt.target.state[StateType.EDITABLE]) {
       this.onEditableChanged_(evt);
       return;
     }

chrome/browser/resources/chromeos/chromevox/cvox2/background/editing_test.extjs

@@ -126,7 +126,6 @@ TEST_F('EditingTest', 'TextButNoSelectionChange', function() {
           .expectBraille('text1 ed', {startIndex: 0, endIndex: 0})
           .call(input.setSelection.bind(input, 5, 5))
           .expectBraille('text2 ed', {startIndex: 5, endIndex: 5})
-          .expectSpeech('text2');
 
       mockFeedback.replay();
     });

chrome/renderer/resources/extensions/automation/automation_node.js

@@ -526,7 +526,7 @@ AutomationNodeImpl.prototype = {
   },
 
   setSelection: function(startIndex, endIndex) {
-    if (this.role == 'textField' || this.role == 'textBox') {
+    if (this.state.editable) {
       this.performAction_('setSelection',
                           { focusNodeID: this.id,
                             anchorOffset: startIndex,