Accessible bounds should include device scale factor on Windows.

content/browser/frame_host/render_frame_host_impl.cc

Index: content/browser/frame_host/render_frame_host_impl.cc
diff --git a/content/browser/frame_host/render_frame_host_impl.cc b/content/browser/frame_host/render_frame_host_impl.cc
index a308aaeebf23045372a49c18a7c104bccbb76b6c..d713df1d1d392c8dd125b9bcb0d05321d12d7097 100644
--- a/content/browser/frame_host/render_frame_host_impl.cc
+++ b/content/browser/frame_host/render_frame_host_impl.cc
@@ -42,6 +42,7 @@
 #include "content/browser/permissions/permission_service_context.h"
 #include "content/browser/permissions/permission_service_impl.h"
 #include "content/browser/presentation/presentation_service_impl.h"
+#include "content/browser/renderer_host/dip_util.h"
 #include "content/browser/renderer_host/input/input_router_impl.h"
 #include "content/browser/renderer_host/input/timeout_monitor.h"
 #include "content/browser/renderer_host/media/media_devices_dispatcher_host.h"
@@ -808,6 +809,13 @@ gfx::Point RenderFrameHostImpl::AccessibilityOriginInScreen(
   return gfx::Point();
 }
 
+float RenderFrameHostImpl::AccessibilityGetDeviceScaleFactor() const {
+  RenderWidgetHostView* view = render_view_host_->GetWidget()->GetView();
+  if (view)
+    return GetScaleFactorForView(view);
+  return 1.0f;
+}
+
 void RenderFrameHostImpl::AccessibilityReset() {
   accessibility_reset_token_ = g_next_accessibility_reset_token++;
   Send(new AccessibilityMsg_Reset(routing_id_, accessibility_reset_token_));