Fix x/y position of gesture scroll events.

content/common/input/synthetic_web_input_event_builders.h

Index: content/common/input/synthetic_web_input_event_builders.h
diff --git a/content/common/input/synthetic_web_input_event_builders.h b/content/common/input/synthetic_web_input_event_builders.h
index ef1a1694bb7ebb4a4f4efe24585387dc65a5a1f4..e865e9b23cedfe6f4f0264b9a43b221ad42563e9 100644
--- a/content/common/input/synthetic_web_input_event_builders.h
+++ b/content/common/input/synthetic_web_input_event_builders.h
@@ -32,6 +32,14 @@ class CONTENT_EXPORT SyntheticWebMouseWheelEventBuilder {
                                          float dy,
                                          int modifiers,
                                          bool precise);
+  static blink::WebMouseWheelEvent Build(float x,
+                                         float y,
+                                         float global_x,
+                                         float global_y,
+                                         float dx,
+                                         float dy,
+                                         int modifiers,
+                                         bool precise);
 };
 
 class CONTENT_EXPORT SyntheticWebKeyboardEventBuilder {