Revert "Use libcros to convert input method ID to keyboard overlay ID."

chrome/browser/chromeos/cros/input_method_library.h

Index: chrome/browser/chromeos/cros/input_method_library.h
diff --git a/chrome/browser/chromeos/cros/input_method_library.h b/chrome/browser/chromeos/cros/input_method_library.h
index 26df7a779a28b2c4ec85271591faf361c797efc8..0c62ead74d192e31c949718726220dbc1260f0c8 100644
--- a/chrome/browser/chromeos/cros/input_method_library.h
+++ b/chrome/browser/chromeos/cros/input_method_library.h
@@ -101,11 +101,6 @@ class InputMethodLibrary {
                             const std::string& config_name,
                             const ImeConfigValue& value) = 0;
 
-  // Returns the keyboard overlay ID corresponding to |input_method_id|.
-  // Returns an empty string if there is no corresponding keyboard overlay ID.
-  virtual std::string GetKeyboardOverlayId(
-      const std::string& input_method_id) = 0;
-
   // Sets the IME state to enabled, and launches its processes if needed.
   virtual void StartInputMethodProcesses() = 0;