Here is the exact Repro steps:

1. Navigate to any Pdf page>> Scroll the page using two finger scrolling on touchapd>> and observe

Able to reproduce the issue on Peppy using 54.0.2800.2/8609.0.0(e46e420e00000000).

Stack Trace(f7f8458200000000):
==============================
Thread 0 CRASHED [SIGILL @ 0xb4c8b7de ] MAGIC SIGNATURE THREAD
0xb4c8b7de	(chrome + 0x028347de )	ui::FlingCurve::FlingCurve(gfx::Vector2dF const&, base::TimeTicks)
0xb4390f9f	(chrome + 0x01f39f9f )	ui::WebGestureCurveImpl::CreateFromDefaultPlatformCurve(gfx::Vector2dF const&, gfx::Vector2dF const&, bool)
0xb3ccd527	(chrome + 0x01876527 )	content::BlinkPlatformImpl::createFlingAnimationCurve(blink::WebGestureDevice, blink::WebFloatPoint const&, blink::WebSize const&)
0xb5e9d957	(chrome + 0x03a46957 )	blink::WebViewImpl::handleGestureEvent(blink::WebGestureEvent const&)
0xb5eb4815	(chrome + 0x03a5d815 )	blink::PageWidgetDelegate::handleInputEvent(blink::PageWidgetEventHandler&, blink::WebInputEvent const&, blink::LocalFrame*)
0xb5e9e859	(chrome + 0x03a47859 )	blink::WebViewImpl::handleInputEvent(blink::WebInputEvent const&)
0xb43ceb39	(chrome + 0x01f77b39 )	content::RenderWidgetInputHandler::HandleInputEvent(blink::WebInputEvent const&, ui::LatencyInfo const&, content::InputEventDispatchType)
0xb441d4d3	(chrome + 0x01fc64d3 )	content::RenderWidget::OnMessageReceived(IPC::Message const&)
0xb441747d	(chrome + 0x01fc047d )	content::RenderViewImpl::OnMessageReceived(IPC::Message const&)
0xb4e7cb27	(chrome + 0x02a25b27 )	IPC::MessageRouter::RouteMessage(IPC::Message const&)
0xb3cd56a5	(chrome + 0x0187e6a5 )	content::ChildThreadImpl::OnMessageReceived(IPC::Message const&)
0xb2b3697b	(chrome + 0x006df97b )	base::debug::TaskAnnotator::RunTask(char const*, base::PendingTask const&)
0xb2c0a055	(chrome + 0x007b3055 )	scheduler::TaskQueueManager::DoWork(base::TimeTicks, bool)
0xb2c09699	(chrome + 0x007b2699 )	base::internal::Invoker<base::internal::BindState<void (scheduler::TaskQueueManager::*)(base::TimeTicks, bool), base::WeakPtr<scheduler::TaskQueueManager>, base::TimeTicks, bool>, void ()>::Run(base::internal::BindStateBase*)
0xb2b3697b	(chrome + 0x006df97b )	base::debug::TaskAnnotator::RunTask(char const*, base::PendingTask const&)
0xb2b2bdc7	(chrome + 0x006d4dc7 )	base::MessageLoop::DoWork()
0xb2b2c299	(chrome + 0x006d5299 )	base::MessagePumpDefault::Run(base::MessagePump::Delegate*)
0xb47b8a4d	(chrome + 0x02361a4d )	base::RunLoop::Run()
0xb442217d	(chrome + 0x01fcb17d )	content::RendererMain(content::MainFunctionParams const&)
0xb45623f9	(chrome + 0x0210b3f9 )	content::RunZygote(content::MainFunctionParams const&, content::ContentMainDelegate*)
0xb45625f9	(chrome + 0x0210b5f9 )	content::ContentMainRunnerImpl::Run()
0xb45616e5	(chrome + 0x0210a6e5 )	content::ContentMain(content::ContentMainParams const&)
0xb2c2bd39	(chrome + 0x007d4d39 )	ChromeMain
0xb1dab307	(libc-2.19.so -libc-start.c:285 )	__libc_start_main
0xb2c2bbfb	(chrome + 0x007d4bfb )	_start
0xb64fbb07	(chrome -elf-init.c:87 )	__libc_csu_init
0xb24409df	(ld-2.19.so + 0x0000b9df )	_dl_sort_fini

Feedback sent 8:45am EDT  Issue#629796 

1. PDF Opens
2. Scroll down
3. Crash

Version 53.0.2785.15 dev
Platform 8530.13.0 (Official Build) dev-channel veyron_minnie
ARC Version 3050391
Firmware Google_Veyron_Minnie.6588.197.0