input: Remove dead code.

content/browser/renderer_host/render_widget_host_view_mac.h

Index: content/browser/renderer_host/render_widget_host_view_mac.h
diff --git a/content/browser/renderer_host/render_widget_host_view_mac.h b/content/browser/renderer_host/render_widget_host_view_mac.h
index a60dce5f3270ac3113faf005e2736643132b030f..2c0d66eedcae138c920bed912e50faad65a1c3f3 100644
--- a/content/browser/renderer_host/render_widget_host_view_mac.h
+++ b/content/browser/renderer_host/render_widget_host_view_mac.h
@@ -323,7 +323,6 @@ class CONTENT_EXPORT RenderWidgetHostViewMac
 
   bool LockMouse() override;
   void UnlockMouse() override;
-  void OnSetNeedsFlushInput() override;
   void GestureEventAck(const blink::WebGestureEvent& event,
                        InputEventAckState ack_result) override;
 
@@ -568,9 +567,6 @@ class CONTENT_EXPORT RenderWidgetHostViewMac
   // Whether a request for begin frames has been issued.
   bool needs_begin_frames_;
 
-  // Whether a request to flush input has been issued.
-  bool needs_flush_input_;
-
   // The background color of the web content. This color will be drawn when the
   // web content is not able to draw in time.
   SkColor background_color_ = SK_ColorTRANSPARENT;