Revert restartInput change off the M57 release branch.

third_party/WebKit/public/web/WebWidgetClient.h

Index: third_party/WebKit/public/web/WebWidgetClient.h
diff --git a/third_party/WebKit/public/web/WebWidgetClient.h b/third_party/WebKit/public/web/WebWidgetClient.h
index 48c1d50f2f8d8430118b487ac1bb8a1f4b49099f..c4e2b44b8e05409dcf3d7ba9ae70824261e2ada0 100644
--- a/third_party/WebKit/public/web/WebWidgetClient.h
+++ b/third_party/WebKit/public/web/WebWidgetClient.h
@@ -106,6 +106,10 @@ class WebWidgetClient {
   // displayed.
   virtual WebScreenInfo screenInfo() { return WebScreenInfo(); }
 
+  // When this method gets called, WebWidgetClient implementation should
+  // reset the input method by cancelling any ongoing composition.
+  virtual void resetInputMethod() {}
+
   // Requests to lock the mouse cursor. If true is returned, the success
   // result will be asynchronously returned via a single call to
   // WebWidget::didAcquirePointerLock() or