Added a system caret used for accessibility on Windows.

content/browser/renderer_host/legacy_render_widget_host_win.h

Index: content/browser/renderer_host/legacy_render_widget_host_win.h
diff --git a/content/browser/renderer_host/legacy_render_widget_host_win.h b/content/browser/renderer_host/legacy_render_widget_host_win.h
index 5c58e15b797f9eb47afc39356193844c7fa532ff..32d387540589b83e9e43894982add95ca361474e 100644
--- a/content/browser/renderer_host/legacy_render_widget_host_win.h
+++ b/content/browser/renderer_host/legacy_render_widget_host_win.h
@@ -24,7 +24,6 @@ class DirectManipulationHelper;
 }  // namespace gfx
 
 namespace ui {
-class AXFakeCaretWin;
 class WindowEventTarget;
 }
 
@@ -121,9 +120,6 @@ class CONTENT_EXPORT LegacyRenderWidgetHostHWND
     host_ = host;
   }
 
-  // Changes the position of the fake caret.
-  void MoveCaretTo(const gfx::Rect& bounds);
-
  protected:
   void OnFinalMessage(HWND hwnd) override;
 
@@ -163,9 +159,6 @@ class CONTENT_EXPORT LegacyRenderWidgetHostHWND
 
   RenderWidgetHostViewAura* host_;
 
-  // Some assistive software need to track the location of the caret.
-  std::unique_ptr<ui::AXFakeCaretWin> ax_fake_caret_;
-
   // This class provides functionality to register the legacy window as a
   // Direct Manipulation consumer. This allows us to support smooth scroll
   // in Chrome on Windows 10.