[Chromecast] Send tap event for mouse left button click

When text field is focused and received double tap, touch exploration
controller send out ax gesture click which triggers this stubbed out
function. The function needs to rewrite a tap gesture for touch explored
components.

Bug: b/195347732
Test: test on device on webview with text field.
Change-Id: I3bdec5ceba4f1387a7aa1ca0476be4bf2de3ef2c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3098047
Reviewed-by: Randy Rossi <rmrossi@chromium.org>
Reviewed-by: Daniel Nicoara <dnicoara@chromium.org>
Commit-Queue: Yuanyao Zhong <yyzhong@google.com>
Cr-Commit-Position: refs/heads/master@{#912688}

chromecast/browser/extensions/api/accessibility_private/accessibility_extension_api.cc

@@ -12,6 +12,13 @@
 #include "content/public/browser/render_frame_host.h"
 #include "extensions/common/image_util.h"
 #include "services/service_manager/public/cpp/interface_provider.h"
+#include "ui/aura/window.h"
+#include "ui/aura/window_tree_host.h"
+#include "ui/display/display.h"
+#include "ui/display/screen.h"
+#include "ui/events/base_event_utils.h"
+#include "ui/events/event.h"
+#include "ui/events/event_constants.h"
 
 namespace {
 
@@ -130,8 +137,51 @@ AccessibilityPrivateSendSyntheticKeyEventFunction::Run() {
 
 ExtensionFunction::ResponseAction
 AccessibilityPrivateSendSyntheticMouseEventFunction::Run() {
-  // Chromecast's touch exploration controller still generates synthetic
-  // mouse events on its own. Do nothing.
+  std::unique_ptr<accessibility_private::SendSyntheticMouseEvent::Params>
+      params = accessibility_private::SendSyntheticMouseEvent::Params::Create(
+          *args_);
+  EXTENSION_FUNCTION_VALIDATE(params);
+  accessibility_private::SyntheticMouseEvent* mouse_data = &params->mouse_event;
+
+  if (mouse_data->type ==
+          accessibility_private::SYNTHETIC_MOUSE_EVENT_TYPE_RELEASE &&
+      mouse_data->mouse_button ==
+          accessibility_private::SYNTHETIC_MOUSE_EVENT_BUTTON_LEFT) {
+    // ui::ET_TOUCH_PRESSED and ui::ET_TOUCH_RELEASED is sent for synthetic
+    // mouse event left button click.
+    ui::PointerDetails pointer_details;
+    pointer_details.pointer_type = ui::EventPointerType::kTouch;
+
+    gfx::Point location(mouse_data->x, mouse_data->y);
+
+    auto* host = chromecast::shell::CastBrowserProcess::GetInstance()
+                     ->accessibility_manager()
+                     ->window_tree_host();
+    DCHECK(host);
+
+    std::unique_ptr<ui::TouchEvent> touch_press =
+        std::make_unique<ui::TouchEvent>(ui::ET_TOUCH_PRESSED, gfx::Point(),
+                                         ui::EventTimeForNow(),
+                                         pointer_details);
+    touch_press->set_location(location);
+    touch_press->set_root_location(location);
+    touch_press->UpdateForRootTransform(
+        host->GetRootTransform(),
+        host->GetRootTransformForLocalEventCoordinates());
+    host->DeliverEventToSink(touch_press.get());
+
+    std::unique_ptr<ui::TouchEvent> touch_release =
+        std::make_unique<ui::TouchEvent>(ui::ET_TOUCH_RELEASED, gfx::Point(),
+                                         ui::EventTimeForNow(),
+                                         pointer_details);
+    touch_release->set_location(location);
+    touch_release->set_root_location(location);
+    touch_release->UpdateForRootTransform(
+        host->GetRootTransform(),
+        host->GetRootTransformForLocalEventCoordinates());
+    host->DeliverEventToSink(touch_release.get());
+  }
+
   return RespondNow(NoArguments());
 }