- Electron version: 0.37.6
- Operating system: Windows 10

In VSCode, in order to support screen readers while editing text, we set the contents of a `<textarea>` to the contents of the line and lines surrounding the cursor and we mirror the editor selection in the `<textarea>` via `setSelectionRange`.

Chromium is not the fastest when it comes to setting large amounts of text :) (such as > 10,000 characters) and basically stalls all the time. Apparently, Electron already has some knowledge about when a screen reader is attached to the main process window (in C++ code). Is it possible to expose this as a getter + event when it first happens in the `electron` API.

We could then maintain this costly `<textarea>` sync only when really needed.

atom/browser/browser.h
bool SetAsDefaultProtocolClient(const std::string& protocol);
  
  bool IsDefaultProtocolClient(const std::string& protocol);
  
  bool SetBadgeCount(int count);
  int GetBadgeCount();
#if defined(OS_MACOSX)
  struct LoginItemSettings {
    bool open_at_login = false;
    bool open_as_hidden = false;
    bool restore_state = false;
    bool opened_at_login = false;
    bool opened_as_hidden = false;
  };
  
  void Hide();
  
  void Show();
  
  void SetUserActivity(const std::string& type,
                       const base::DictionaryValue& user_info,
                       mate::Arguments* args);
  
  std::string GetCurrentActivityType();
  
  bool ContinueUserActivity(const std::string& type,
                            const base::DictionaryValue& user_info);
  
  enum BounceType {