Able to reproduce the issue on Windows-10 and Mac OS 10.11.6 using chrome latest Dev M55-55.0.2855.0. Observed browser crash while clicking on clear and reset from all sites.

Stack Trace:
=============
Thread 0 CRASHED [SIGILL @ 0x00007f9c1536f2c2 ] MAGIC SIGNATURE THREAD
0x00007f9c1536f2c2	(chrome -./out/Release/../../chrome/browser/ui/webui/settings/site_settings_handler.cc:439 )	settings::SiteSettingsHandler::HandleResetCategoryPermissionForOrigin
0x00007f9c152e920f	(chrome + 0x038d120f )	
0x00007f9c152e79e1	(chrome -./out/Release/../../build/linux/debian_wheezy_amd64-sysroot/usr/lib/gcc/x86_64-linux-gnu/4.6/../../../../include/c++/4.6/bits/basic_string.h:244 )	GetWebUIFactoryFunction
0x00007f9c152e61d6	(chrome -./out/Release/../../chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc:640 )	ChromeWebUIControllerFactory::GetWebUIType
0x00007f9c152e9e95	(chrome -./out/Release/../../chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc:646 )	ChromeWebUIControllerFactory::UseWebUIForURL
0x00007f9c125ebea7	(chrome -./out/Release/../../build/linux/debian_wheezy_amd64-sysroot/usr/lib/gcc/x86_64-linux-gnu/4.6/../../../../include/c++/4.6/bits/char_traits.h:257 )	<name omitted>
0x00007f9c132ae695	(chrome -./out/Release/../../base/callback.h:61 )	<name omitted>
0x00007f9c132aeddf	(chrome + 0x01896ddf )	
0x00007f9c132aef12	(chrome -./out/Release/../../base/tuple.h:144 )	<name omitted>
0x00007f9c132aed6f	(chrome -./out/Release/../../content/browser/webui/web_ui_impl.cc:91 )	<name omitted>
0x00007f9c17a214e4	(chrome + 0x060094e4 )	_fini
0x00007f9c17a21f01	(chrome + 0x06009f01 )	_fini
0x00007f9c132aed20	(chrome -./out/Release/../../content/browser/webui/web_ui_impl.cc:91 )	<name omitted>
0x00007f9c1329af16	(chrome -./out/Release/../../content/browser/web_contents/web_contents_impl.cc:654 )	<name omitted>
0x00007f9c13b9bf8f	(chrome + 0x02183f8f )	
0x00007f9c131db362	(chrome -./out/Release/../../content/browser/renderer_host/render_view_host_impl.cc:836 )	<name omitted>
0x00007f9c131c89ce	(chrome -./out/Release/../../content/browser/renderer_host/render_widget_host_impl.cc:459 )	<name omitted>
0x00007f9c0b54a46c	(libc-2.19.so -clock_gettime.c:115 )	__clock_gettime
0x000026d5d27376ff		
0x00007f9c131b8c52	(chrome -./out/Release/../../content/browser/renderer_host/render_process_host_impl.cc:1964 )	<name omitted>
0x00007f9c0b54a46c	(libc-2.19.so -clock_gettime.c:115 )	__clock_gettime
0x00007f9c13bd1b52	(chrome -./out/Release/../../base/time/time_posix.cc:98 )	<name omitted>
0x00007f9c13bf8562	(chrome -./out/Release/../../base/profiler/tracked_time.cc:51 )	<name omitted>
0x00007f9c143d1899	(chrome -./out/Release/../../ipc/ipc_channel_proxy.cc:314 )	<name omitted>
0x00007f9c17a7f110	(chrome + 0x06067110 )	_fini
0x00007f9c13bf3a12	(chrome -./out/Release/../../base/callback.h:61 )	<name omitted>
0x00007f9c143d16ba	(chrome -./out/Release/../../ipc/ipc_channel_proxy.cc:128 )	<name omitted>
0x00007f9c17a7f110	(chrome + 0x06067110 )	_fini
0x00007f9c17ad43e8	(chrome + 0x060bc3e8 )	_fini
0x00007f9c13b97188	(chrome -./out/Release/../../base/message_loop/message_loop.cc:488 )	<name omitted>
0x00007f9c115e48b8	(libpthread-2.19.so + 0x0000f8b8 )	
0x00007f9c115e48b8	(libpthread-2.19.so + 0x0000f8b8 )	
0x00007f9c0a535068	(libxcb.so.1.1.0 + 0x0000c068 )	
0x00007f9c115e48b8	(libpthread-2.19.so + 0x0000f8b8 )	
0x00007f9c17ad43e8	(chrome + 0x060bc3e8 )	_fini
0x00007f9c13b974e7	(chrome -./out/Release/../../base/message_loop/message_loop.cc:497 )	<name omitted>
0x00007f9c13b96bda	(chrome -./out/Release/../../base/message_loop/message_loop.cc:621 )	<name omitted>
0x00007f9c12688e7f	(chrome + 0x00c70e7f )	
0x00007f9c17ad4407	(chrome + 0x060bc407 )	_fini
0x00007f9c17ad43e8	(chrome + 0x060bc3e8 )	_fini
0x00007f9c143d16ba	(chrome -./out/Release/../../ipc/ipc_channel_proxy.cc:128 )	<name omitted>
0x00007f9c12688e7f	(chrome + 0x00c70e7f )	
0x00007f9c17ad4407	(chrome + 0x060bc407 )	_fini
0x00007f9c17ad43e8	(chrome + 0x060bc3e8 )	_fini
0x00007f9c143d16ba	(chrome -./out/Release/../../ipc/ipc_channel_proxy.cc:128 )	<name omitted>
0x00007f9c10211bb7	(libX11.so.6.3.0 + 0x0003bbb7 )	
0x00007f9c10211cfb	(libX11.so.6.3.0 + 0x0003bcfb )	
0x00007f9c13b989af	(chrome + 0x021809af )	
0x00007f9c13b989c8	(chrome -./out/Release/../../base/message_loop/message_pump_glib.cc:267 )	WorkSourceDispatch
0x00007f9c10553e03	(libglib-2.0.so.0.4002.0 + 0x00048e03 )	
0x00007f9c10562b3f	(libglib-2.0.so.0.4002.0 + 0x00057b3f )	
0x00007f9c10554047	(libglib-2.0.so.0.4002.0 + 0x00049047 )	
0x00007f9c105540eb	(libglib-2.0.so.0.4002.0 + 0x000490eb )	
0x00007f9c13b988b5	(chrome -./out/Release/../../base/message_loop/message_pump_glib.cc:309 )	base::MessagePumpGlib::Run
0x00007f9c1250beff	(chrome + 0x00af3eff )	
0x00007f9c1250bf83	(chrome + 0x00af3f83 )	
0x00007f9c13bb0a6d	(chrome -./out/Release/../../base/run_loop.cc:35 )	<name omitted>
0x00007f9c13a61e61	(chrome -./out/Release/../../chrome/browser/chrome_browser_main.cc:2098 )	ChromeBrowserMainParts::MainMessageLoopRun
0x00007f9c12fbf2cb	(chrome -./out/Release/../../content/browser/browser_main_runner.cc:64 )	content::BrowserMainRunnerImpl::Initialize
0x00007f9c1250bf83	(chrome + 0x00af3f83 )	
0x00007f9c12fb6587	(chrome -./out/Release/../../content/browser/browser_main_loop.cc:954 )	content::BrowserMainLoop::RunMainMessageLoopParts
0x00007f9c12fbf3dc	(chrome -./out/Release/../../content/browser/browser_main_runner.cc:155 )	content::BrowserMainRunnerImpl::Run
0x00007f9c12fb0ca8	(chrome -./out/Release/../../content/browser/browser_main.cc:46 )	content::BrowserMain
0x00007f9c13836a76	(chrome -./out/Release/../../content/app/content_main_runner.cc:405 )	content::RunNamedProcessTypeMain
0x00007f9c13837386	(chrome -./out/Release/../../content/app/content_main_runner.cc:786 )	content::ContentMainRunnerImpl::Run
0x00007f9c13838f3d	(chrome -./out/Release/../../content/app/content_main.cc:20 )	content::ContentMain
0x00007f9c125155ba	(chrome -./out/Release/../../chrome/app/chrome_main.cc:85 )	ChromeMain
0x00007f9c0b462ec4	(libc-2.19.so -libc-start.c:287 )	__libc_start_main
0x00007f9c1250bfac	(chrome + 0x00af3fac )	_start

Manual bisect info:
Good build:55.0.2850.0
Bad build:55.0.2851.0

Unable to do tool bisect as links are not seen in chromium builds.Hence providing Manual Changelog URL.

CHANGELOG URL: https://chromium.googlesource.com/chromium/src/+log/55.0.2850.0..55.0.2851.0?pretty=fuller&n=10000

Suspecting https://codereview.chromium.org/2298283002 from changelog.

@finnur: Please feel free to re-assign if this is not related to your change.

Adding Release Blocker label as this is a recent regression.

Issue is also seen in chrome://md-settings/siteSettings/notifications page

Steps:
(1)Navigate to chrome://md-settings/notifications page
(2)Click on 'More Actions' Menu at 'Allow' section -> Now select 'Block' or 'Allow' options  and observe Browser crash

Crash Id:
74504d1500000000

Attaching Video for reference

Deleted: Actual_Crash.ogv 2.5 MB

	Actual_Crash.ogv 2.5 MB View Download

finnur@, Gentle ping! could you please look into this?

Thank you!

There's two bugs on a crash similar to this. One I've fixed yesterday ( issue 644998 ) and one I'm waiting on review to fix ( issue 646801 ). I think we might be conflating these two issues in this bug, but in any case I think the issues are under control and we don't need this bug to keep track of it also.