Media Controls: move timeline related code to modules.

third_party/WebKit/Source/modules/media_controls/elements/MediaControlElementsHelper.h

Index: third_party/WebKit/Source/modules/media_controls/elements/MediaControlElementsHelper.h
diff --git a/third_party/WebKit/Source/modules/media_controls/elements/MediaControlElementsHelper.h b/third_party/WebKit/Source/modules/media_controls/elements/MediaControlElementsHelper.h
index 0f00c740f440876c9903cdcc2d1b0334cf2471ca..557ba729d8fc35a8977f5eca22429ac27862a7ae 100644
--- a/third_party/WebKit/Source/modules/media_controls/elements/MediaControlElementsHelper.h
+++ b/third_party/WebKit/Source/modules/media_controls/elements/MediaControlElementsHelper.h
@@ -10,6 +10,7 @@
 namespace blink {
 
 class Event;
+class LayoutObject;
 
 // Helper class for media control elements. It contains methods, constants or
 // concepts shared by more than one element.
@@ -18,6 +19,10 @@ class MediaControlElementsHelper final {
 
  public:
   static bool IsUserInteractionEvent(Event*);
+
+  // Sliders (the volume control and timeline) need to capture some additional
+  // events used when dragging the thumb.
+  static bool IsUserInteractionEventForSlider(Event*, LayoutObject*);
 };
 
 }  // namespace blink