Add development Blink setting for impl-side rubber-banding

Source/core/frame/Settings.in

 # Defines properties which are available on the Settings object.
 #
 # Please think carefully before adding a new Setting.  Some questions to
 # consider are:
 # - Should this be a RuntimeEnabledFeature instead? Settings are for things
 #   which we support either values of at runtime.  Features are set at renderer
 #   process startup and are never changed. Features also tend to be set to a
 #   value based on the platform or the stability of the code in question, where
 #   as settings both codepaths need to be stable.
 # - How will you ensure test coverage of all relevant values of your setting?
@@ skipping 206 matching lines @@
 # Settings for experimental desktop pinch-zoom support (with semantics
 # optimized for large screens).  Pinch-zoom generally is implemented mainly
 # outside of blink (in the compositor) and doesn't require any settings.
 # These settings are for an experimental modification to how pinch-zoom
 # behaves.  TODO(wjmaclean): link to design document.
 # crbug.com/304869 tracks removal.
 pinchVirtualViewportEnabled initial=false
 useSolidColorScrollbars initial=false
 pinchOverlayScrollbarThickness type=int, initial=0
 
+# The rubber-band overscroll effect is implemented in Blink and is being moved
+# to the compositor thread. This will be set to true and eventually removed.
+# crbug.com/133097
+rubberBandingOnCompositorThread initial=false
+
 mainFrameClipsContent initial=true
 
 
 # Presumably used by LayoutTests?  Unclear.
 useWideViewport initial=true, invalidate=ViewportDescription
 loadWithOverviewMode initial=true, invalidate=ViewportDescription
 
 
 # Font scale factor for accessibility, applied as part of text autosizing.
 accessibilityFontScaleFactor type=double, initial=1.0, invalidate=TextAutosizing
@@ skipping 61 matching lines @@
 primaryHoverType type=HoverType, initial=HoverTypeNone, invalidate=MediaQuery
 
 # Whether accessibility support is enabled at all.
 accessibilityEnabled initial=false, invalidate=AccessibilityState
 
 # If true, the value in password fields is exposed to assistive technologies.
 accessibilityPasswordValuesEnabled initial=false
 
 # If true, static text nodes expose inline text box children.
 inlineTextBoxAccessibilityEnabled initial=false