provide output for table column headers

Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I364949b358db73b125d7687b73bf2239648352d1
Reviewed-on: https://chromium-review.googlesource.com/887426Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Reviewed-by: Michael Giuffrida <michaelpg@chromium.org>
Commit-Queue: David Tseng <dtseng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#532918}

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

@@ -1394,3 +1394,43 @@ TEST_F('BackgroundTest', 'TextSelectionAndLiveRegion', function() {
         .replay();
   });
 });
+
+TEST_F('BackgroundTest', 'TableColumnHeaders', function() {
+  var mockFeedback = this.createMockFeedback();
+  this.runWithLoadedTree(function(root) {/*!
+    <div role="grid">
+      <div role="rowgroup">
+        <div role="row">
+          <div role="columnheader">city</div>
+          <div role="columnheader">state</div>
+          <div role="columnheader">zip</div>
+        </div>
+      </div>
+      <div role="rowgroup">
+        <div role="row">
+          <div role="gridcell">Mountain View</div>
+          <div role="gridcell">CA</div>
+          <div role="gridcell">94043</div>
+        </div>
+        <div role="row">
+          <div role="gridcell">San Jose</div>
+          <div role="gridcell">CA</div>
+          <div role="gridcell">95128</div>
+        </div>
+      </div>
+    </div>
+  */}, function(root) {
+    mockFeedback.call(doCmd('nextRow'))
+        .expectSpeech('Mountain View', 'row 2 column 1')
+        .call(doCmd('nextRow'))
+        .expectNextSpeechUtteranceIsNot('city')
+        .expectSpeech('San Jose', 'row 3 column 1')
+        .call(doCmd('nextCol'))
+        .expectSpeech('CA', 'row 3 column 2', 'state')
+        .call(doCmd('previousRow'))
+        .expectSpeech('CA', 'row 2 column 2')
+        .call(doCmd('previousRow'))
+        .expectSpeech('state', 'row 1 column 2')
+        .replay();
+  });
+});

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

@@ -1211,10 +1211,41 @@ Output.prototype = {
                 buff);
           }
         } else if (token == 'node') {
-          if (!tree.firstChild || !node[tree.firstChild.value])
+          if (!tree.firstChild)
             return;
-          var related = node[tree.firstChild.value];
-          this.node_(related, related, Output.EventType.NAVIGATE, buff);
+
+          var relationName = tree.firstChild.value;
+          if (node[relationName]) {
+            var related = node[relationName];
+            this.node_(related, related, Output.EventType.NAVIGATE, buff);
+          } else if (
+              relationName == 'tableColumnHeader' &&
+              node.role == RoleType.CELL) {
+            // Because table columns do not contain cells as descendants, we
+            // must search for the correct column.
+            var columnIndex = node.tableCellColumnIndex;
+            if (opt_prevNode) {
+              // Skip output when previous position falls on the same column.
+              while (opt_prevNode &&
+                     !AutomationPredicate.cellLike(opt_prevNode)) {
+                opt_prevNode = opt_prevNode.parent;
+              }
+
+              if (opt_prevNode &&
+                  opt_prevNode.tableCellColumnIndex == columnIndex)
+                return;
+            }
+            var tableLike = node.parent && node.parent.parent;
+            if (!tableLike || !AutomationPredicate.table(tableLike))
+              return;
+            var column = tableLike.children.find(function(candidate) {
+              return columnIndex === candidate.tableColumnIndex;
+            });
+            if (column && column.tableColumnHeader &&
+                column.tableColumnHeader.name) {
+              this.append_(buff, column.tableColumnHeader.name, options);
+            }
+          }
         } else if (token == 'nameOrTextContent') {
           if (node.name) {
             this.format_(node, '$name', buff);

chrome/common/extensions/api/automation.idl

@@ -611,6 +611,12 @@
     // The corresponding row header for this cell.
     AutomationNode? tableRowHeader;
 
+    // The column index of this column node.
+    long? tableColumnIndex;
+
+    // The row index of this row node.
+    long? tableRowIndex;
+
     //
     // Live region attributes.
     //

third_party/closure_compiler/externs/automation.js

@@ -837,6 +837,20 @@ chrome.automation.AutomationNode.prototype.tableColumnHeader;
  */
 chrome.automation.AutomationNode.prototype.tableRowHeader;
 
+/**
+ * The column index of this column node.
+ * @type {(number|undefined)}
+ * @see https://developer.chrome.com/extensions/automation#type-tableColumnIndex
+ */
+chrome.automation.AutomationNode.prototype.tableColumnIndex;
+
+/**
+ * The row index of this row node.
+ * @type {(number|undefined)}
+ * @see https://developer.chrome.com/extensions/automation#type-tableRowIndex
+ */
+chrome.automation.AutomationNode.prototype.tableRowIndex;
+
 /**
  * The type of region if this is the root of a live region. Possible values are 'polite' and 'assertive'.
  * @type {(string|undefined)}