Make ChromeVox respond to all in-page link navigations.

Previously ChromeVox handled in-page links if you force-click on
them. This change makes it so that it also handles it if the user
presses Enter or mouse-clicks on a link, by responding to the
scrolledToAnchor event.

Testing this required enabling the test server because the browser
doesn't follow same-page links in data urls. Some of the work to
make use of the test server in ChromeVox tests was already done
for portals, but I had to fix a tiny bug in js2gtest.

how they're activated.

Bug: 1130786
AX-Relnotes: ChromeVox now properly handles in-page links no matter
Change-Id: I9e56f6c88fdbce35c14e692411cb7bb4a2e46db2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2422704
Commit-Queue: Dominic Mazzoni <dmazzoni@chromium.org>
Reviewed-by: David Tseng <dtseng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#809223}

chrome/browser/resources/chromeos/accessibility/chromevox/background/background_test.js

@@ -136,6 +136,16 @@ ChromeVoxBackgroundTest = class extends ChromeVoxNextE2ETest {
   }
 };
 
+/**
+ * Specific test fixture for tests that need a test server running.
+ */
+ChromeVoxBackgroundTestWithTestServer = class extends ChromeVoxBackgroundTest {
+  get testServer() {
+    return true;
+  }
+};
+
+
 
 /** Tests that ChromeVox classic is in this context. */
 SYNC_TEST_F('ChromeVoxBackgroundTest', 'ClassicNamespaces', function() {
@@ -1230,7 +1240,9 @@ TEST_F('ChromeVoxBackgroundTest', 'BrailleCaretNavigation', function() {
       });
 });
 
-TEST_F('ChromeVoxBackgroundTest', 'InPageLinks', function() {
+// This tests ChromeVox's special support for following an in-page link
+// if you force-click on it. Compare with InPageLinks, below.
+TEST_F('ChromeVoxBackgroundTest', 'ForceClickInPageLinks', function() {
   const mockFeedback = this.createMockFeedback();
   this.runWithLoadedTree(
       `
@@ -1245,6 +1257,29 @@ TEST_F('ChromeVoxBackgroundTest', 'InPageLinks', function() {
       });
 });
 
+// This tests ChromeVox's handling of the scrolledToAnchor event, which is
+// fired when the users follows an in-page link or the document otherwise
+// gets navigated to an in-page link target by the url fragment changing,
+// not necessarily due to directly clicking on the link via ChromeVox.
+//
+// Note: this test needs the test server running because the browser
+// does not follow same-page links on data urls (because it modifies the
+// url fragment, and any change to the url is disallowed for a data url).
+TEST_F('ChromeVoxBackgroundTestWithTestServer', 'InPageLinks', function() {
+  const mockFeedback = this.createMockFeedback();
+  this.runWithLoadedTree(undefined, function(root) {
+    mockFeedback.call(doCmd('nextObject'))
+        .expectSpeech('Jump', 'Internal link')
+        .call(press(KeyCode.RETURN))
+        .expectSpeech('Found It')
+        .call(doCmd('nextHeading'))
+        .expectSpeech('Continue Here', 'Heading 2')
+        .replay();
+  }.bind(this), {
+    url: `${testRunnerParams.testServerBaseUrl}accessibility/in_page_links.html`
+  });
+});
+
 TEST_F('ChromeVoxBackgroundTest', 'ListItem', function() {
   this.resetContextualOutput();
   const mockFeedback = this.createMockFeedback();

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

@@ -76,6 +76,8 @@ DesktopAutomationHandler = class extends BaseAutomationHandler {
     this.addListener_(EventType.MENU_START, this.onMenuStart);
     this.addListener_(
         EventType.SCROLL_POSITION_CHANGED, this.onScrollPositionChanged);
+    // Called when a same-page link is followed or the url fragment changes.
+    this.addListener_(EventType.SCROLLED_TO_ANCHOR, this.onEventDefault);
     this.addListener_(EventType.SELECTION, this.onSelection);
     this.addListener_(EventType.TEXT_CHANGED, this.onEditableChanged_);
     this.addListener_(

chrome/test/base/js2gtest.js

@@ -404,8 +404,8 @@ function TEST_F(testFixture, testFunction, testBody, opt_preamble) {
     const featureList = this[testFixture].prototype.featureList;
     const featuresWithParameters =
         this[testFixture].prototype.featuresWithParameters;
-    if ((!hasSwitches && !featureList && !featuresWithParameters) ||
-        typedefCppFixture == 'V8UnitTest') {
+    if ((!hasSwitches && !featureList && !featuresWithParameters &&
+         !testServer) || typedefCppFixture == 'V8UnitTest') {
       output(`
 typedef ${typedefCppFixture} ${testFixture};
 `);

chrome/test/data/accessibility/in_page_links.html

+    <div><button>Initial button</button>
+    <div><a href="#there">Jump</a></div>
+    <h2>Skip Me</h2>
+    <h2>Skip Me Too</h2>
+    <h2><span id="there">Found It</span></h2>
+    <h2>Continue Here</h2>