ChromeVox: send mousemove as AutomationEvent

We had some issues handling mouse move events as UI events, so fire an
AutomationEvent instead. Makes mouse_handler.js a BaseAutomationHandler.

As a follow-up, let's experiment with rate-limiting these events, since
they seem to come in more frequently than the dom events did.

Bug: 853581
Change-Id: I0606421e5284fcb9803c6428d51b7288393babd9
Reviewed-on: https://chromium-review.googlesource.com/c/1287098
Commit-Queue: James Wallace-Lee <jamwalla@chromium.org>
Reviewed-by: David Tseng <dtseng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#601325}

chrome/browser/chromeos/accessibility/spoken_feedback_event_rewriter_delegate.cc

@@ -7,6 +7,7 @@
 #include "ash/public/interfaces/constants.mojom.h"
 #include "chrome/browser/chromeos/accessibility/accessibility_manager.h"
 #include "chrome/browser/chromeos/accessibility/event_handler_common.h"
+#include "chrome/browser/ui/aura/accessibility/automation_manager_aura.h"
 #include "content/public/browser/native_web_keyboard_event.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/service_manager_connection.h"
@@ -48,13 +49,10 @@ void SpokenFeedbackEventRewriterDelegate::DispatchKeyEventToChromeVox(
 
 void SpokenFeedbackEventRewriterDelegate::DispatchMouseEventToChromeVox(
     std::unique_ptr<ui::Event> event) {
-  extensions::ExtensionHost* host = chromeos::GetAccessibilityExtensionHost(
-      extension_misc::kChromeVoxExtensionId);
-  if (!host)
-    return;
-
-  // Forward the event to ChromeVox's background page.
-  chromeos::ForwardMouseToExtension(*(event->AsMouseEvent()), host);
+  if (event->type() == ui::ET_MOUSE_MOVED) {
+    AutomationManagerAura::GetInstance()->HandleEvent(
+        ax::mojom::Event::kMouseMoved);
+  }
 }
 
 bool SpokenFeedbackEventRewriterDelegate::ShouldDispatchKeyEventToChromeVox(

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

@@ -8,13 +8,18 @@
 
 goog.provide('BackgroundMouseHandler');
 
+goog.require('BaseAutomationHandler');
+
+var AutomationEvent = chrome.automation.AutomationEvent;
 var EventType = chrome.automation.EventType;
 
-/** @constructor */
+/**
+ * @constructor
+ * @extends {BaseAutomationHandler}
+ */
 BackgroundMouseHandler = function() {
-  document.addEventListener('mousemove', this.onMouseMove.bind(this));
-
   chrome.automation.getDesktop(function(desktop) {
+    BaseAutomationHandler.call(this, desktop);
     /**
      *
      * The desktop node.
@@ -22,18 +27,18 @@ BackgroundMouseHandler = function() {
      * @private {!chrome.automation.AutomationNode}
      */
     this.desktop_ = desktop;
+    this.addListener_(EventType.MOUSE_MOVED, this.onMouseMove);
   }.bind(this));
 };
 
 BackgroundMouseHandler.prototype = {
+  __proto__: BaseAutomationHandler.prototype,
+
   /**
    * Handles mouse move events.
-   * @param {Event} evt The mouse move event to process.
-   * @return {boolean} True if the default action should be performed.
+   * @param {AutomationEvent} evt The mouse move event to process.
    */
   onMouseMove: function(evt) {
-    // Immediately save the most recent mouse coordinates.
-    this.desktop_.hitTest(evt.screenX, evt.screenY, EventType.HOVER);
-    return false;
+    this.desktop_.hitTest(evt.mouseX, evt.mouseY, EventType.HOVER);
   },
 };

chrome/browser/ui/aura/accessibility/automation_manager_aura.cc

@@ -92,6 +92,15 @@ void AutomationManagerAura::HandleEvent(views::View* view,
                      weak_ptr_factory_.GetWeakPtr(), id, event_type));
 }
 
+void AutomationManagerAura::HandleEvent(ax::mojom::Event event_type) {
+#if defined(OS_CHROMEOS)
+  aura::Window* root_window = ash::wm::GetActiveWindow();
+  views::Widget* widget = views::Widget::GetWidgetForNativeView(root_window);
+  if (widget)
+    HandleEvent(widget->GetRootView(), event_type);
+#endif
+}
+
 void AutomationManagerAura::SendEventOnObjectById(int32_t id,
                                                   ax::mojom::Event event_type) {
   views::AXAuraObjWrapper* obj = views::AXAuraObjCache::GetInstance()->Get(id);

chrome/browser/ui/aura/accessibility/automation_manager_aura.h

@@ -50,6 +50,9 @@ class AutomationManagerAura : public ui::AXHostDelegate,
   // Handle an event fired upon a |View|.
   void HandleEvent(views::View* view, ax::mojom::Event event_type);
 
+  // Handle an event fired upon the root view.
+  void HandleEvent(ax::mojom::Event event_type);
+
   void HandleAlert(const std::string& text);
 
   // AXHostDelegate implementation.