Added a class acting as a fake caret for accessibility.

content/browser/renderer_host/render_widget_host_view_aura.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/renderer_host/render_widget_host_view_aura.h"
 
 #include <set>
 #include <utility>
 
 #include "base/auto_reset.h"
@@ skipping 874 matching lines @@
 
 void RenderWidgetHostViewAura::UpdateMouseLockRegion() {
   RECT window_rect =
       display::Screen::GetScreen()
           ->DIPToScreenRectInWindow(window_, window_->GetBoundsInScreen())
           .ToRECT();
   ::ClipCursor(&window_rect);
 }
 
 void RenderWidgetHostViewAura::OnLegacyWindowDestroyed() {
-  legacy_render_widget_host_HWND_ = NULL;
+  legacy_render_widget_host_HWND_ = nullptr;
   legacy_window_destroyed_ = true;
 }
 #endif
 
 void RenderWidgetHostViewAura::DidCreateNewRendererCompositorFrameSink(
     cc::mojom::MojoCompositorFrameSinkClient* renderer_compositor_frame_sink) {
   renderer_compositor_frame_sink_ = renderer_compositor_frame_sink;
   if (delegated_frame_host_) {
     delegated_frame_host_->DidCreateNewRendererCompositorFrameSink(
         renderer_compositor_frame_sink_);
@@ skipping 1438 matching lines @@
 void RenderWidgetHostViewAura::OnSelectionBoundsChanged(
     TextInputManager* text_input_manager,
     RenderWidgetHostViewBase* updated_view) {
   if (GetInputMethod())
     GetInputMethod()->OnCaretBoundsChanged(this);
 }
 
 void RenderWidgetHostViewAura::OnTextSelectionChanged(
     TextInputManager* text_input_manager,
     RenderWidgetHostViewBase* updated_view) {
-#if defined(USE_X11) && !defined(OS_CHROMEOS)
   if (!GetTextInputManager())
     return;
 
   // We obtain the TextSelection from focused RWH which is obtained from the
   // frame tree. BrowserPlugin-based guests' RWH is not part of the frame tree
   // and the focused RWH will be that of the embedder which is incorrect. In
   // this case we should use TextSelection for |this| since RWHV for guest
   // forwards text selection information to its platform view.
   RenderWidgetHostViewBase* focused_view =
       is_guest_view_hack_ ? this : GetFocusedWidget()
                                        ? GetFocusedWidget()->GetView()
                                        : nullptr;
 
   if (!focused_view)
     return;
 
+#if defined(USE_X11) && !defined(OS_CHROMEOS)
   const TextInputManager::TextSelection* selection =
       GetTextInputManager()->GetTextSelection(focused_view);
   if (selection->selected_text().length()) {
     // Set the CLIPBOARD_TYPE_SELECTION to the ui::Clipboard.
     ui::ScopedClipboardWriter clipboard_writer(ui::CLIPBOARD_TYPE_SELECTION);
     clipboard_writer.WriteText(selection->selected_text());
   }
-#endif  // defined(USE_X11) && !defined(OS_CHROMEOS)
+
+#elif defined(OS_WIN)
+  // Some assistive software need to track the location of the caret.
+  if (!GetRenderWidgetHost() || !legacy_render_widget_host_HWND_)
+    return;
+
+  // Not using |GetCaretBounds| because it includes the whole of the selection,
+  // not just the focus.
+  const TextInputManager::SelectionRegion* region =
+      GetTextInputManager()->GetSelectionRegion(focused_view);
+  if (!region)
+    return;
+  const gfx::Rect caret_rect = ConvertRectToScreen(gfx::Rect(
+      region->focus.edge_top_rounded().x(),
+      region->focus.edge_top_rounded().y(), 1, region->focus.GetHeight()));
+  legacy_render_widget_host_HWND_->MoveCaretTo(caret_rect);
+#endif  // defined(OS_WIN)
 }
 
 void RenderWidgetHostViewAura::SetPopupChild(
     RenderWidgetHostViewAura* popup_child_host_view) {
   popup_child_host_view_ = popup_child_host_view;
   event_handler_->SetPopupChild(
       popup_child_host_view,
       popup_child_host_view ? popup_child_host_view->event_handler() : nullptr);
 }
 
 void RenderWidgetHostViewAura::UpdateNeedsBeginFramesInternal() {
   if (!delegated_frame_host_)
     return;
   delegated_frame_host_->SetNeedsBeginFrames(needs_begin_frames_ ||
                                              needs_flush_input_);
 }
 
 }  // namespace content