input: Change how synthesized events are dispatched in telemetry tests.

content/browser/renderer_host/input/synthetic_gesture_target.h

Index: content/browser/renderer_host/input/synthetic_gesture_target.h
diff --git a/content/browser/renderer_host/input/synthetic_gesture_target.h b/content/browser/renderer_host/input/synthetic_gesture_target.h
index da44ba2e3be5c3349ca5765ce8a02c40390da3a0..c364fad992f292e4ecdce456eb532987b8c97b98 100644
--- a/content/browser/renderer_host/input/synthetic_gesture_target.h
+++ b/content/browser/renderer_host/input/synthetic_gesture_target.h
@@ -27,10 +27,6 @@ class CONTENT_EXPORT SyntheticGestureTarget {
   virtual void DispatchInputEventToPlatform(
       const blink::WebInputEvent& event) = 0;
 
-  // Called by SyntheticGestureController to request a flush at a time
-  // appropriate for the platform, e.g. aligned with vsync.
-  virtual void SetNeedsFlush() = 0;
-
   // Returns the default gesture source type for the target.
   virtual SyntheticGestureParams::GestureSourceType
       GetDefaultSyntheticGestureSourceType() const = 0;