Ballistic simulations may be created too frequently #11599
Description
Make a normal fling gesture.
~50% of the time, many goBallistic calls are triggered when I would have expected just one.
In this example, it took 78ms cumulative recreating the simulations and causes frame drops.
Call stack
#0 ScrollPositionWithSingleContext.goBallistic (package:flutter/src/widgets/scroll_position_with_single_context.dart:150:16)
#1 BallisticScrollActivity.applyNewDimensions (package:flutter/src/widgets/scroll_activity.dart:399:14)
#2 ScrollPosition.applyNewDimensions (package:flutter/src/widgets/scroll_position.dart:441:14)
#3 ScrollPositionWithSingleContext.applyNewDimensions (package:flutter/src/widgets/scroll_position_with_single_context.dart:110:29)
#4 ScrollPosition.applyContentDimensions (package:flutter/src/widgets/scroll_position.dart:411:7)
#5 RenderViewport.performLayout (package:flutter/src/rendering/viewport.dart:827:20)
#6 RenderObject._layoutWithoutResize (package:flutter/src/rendering/object.dart:1767:7)
#7 PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:1056:18)
#8 BindingBase&SchedulerBinding&GestureBinding&ServicesBinding&RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:251:19)
#9 BindingBase&SchedulerBinding&GestureBinding&ServicesBinding&RendererBinding&WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:504:22)
#10 BindingBase&SchedulerBinding&GestureBinding&ServicesBinding&RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:189:5)
#11 BindingBase&SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:695:15)
#12 BindingBase&SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:643:9)
#13 _invoke (file:///Users/xster/development/flutter/bin/cache/pkg/sky_engine/lib/ui/hooks.dart:86)
#14 _drawFrame (file:///Users/xster/development/flutter/bin/cache/pkg/sky_engine/lib/ui/hooks.dart:75)