Crash ID : 4127dfe1df449b20 (Local Crash ID: 1c3cb60f-e62f-4a55-83e9-c673b553a7a8)

This is a regression issue, broken in M-68 and below is the bisect info:
Good Build : 68.0.3410.0 (Revision : 554250)
Bad Build : 68.0.3413.0 (Revision : 554607)

Change log URL :
https://chromium.googlesource.com/chromium/src/+log/7270258e2271da0a2fc622c2e8dd9fa9e059f49c..823846f493cd328447473fdc011a35912c39b6b6

Suspect : https://chromium.googlesource.com/chromium/src/+/823846f493cd328447473fdc011a35912c39b6b6

@Saman : Could you please check whether this is caused with respect to your change, if not please help us in assigning it to the right owner.

Note : Able to reproduce this crash on Dev build #68.0.3438.3 as well

Stack trace for the crash id(4127dfe1df449b20)
------------------------------
Thread 0 (id: 5676) CRASHED [EXCEPTION_ACCESS_VIOLATION_READ @ 0x00000000 ] MAGIC SIGNATURE THREAD
Stack Quality100%Show frame trust levels
0x00007ffbd72f90ae	(chrome.dll -devtools_eye_dropper.cc:65 )	DevToolsEyeDropper::AttachToHost(content::RenderWidgetHost *)
0x00007ffbd72f8e5c	(chrome.dll -devtools_eye_dropper.cc:43 )	DevToolsEyeDropper::DevToolsEyeDropper(content::WebContents *,base::RepeatingCallback<void >)
0x00007ffbd6dede1e	(chrome.dll -devtools_window.cc:1409 )	DevToolsWindow::SetEyeDropperActive(bool)
0x00007ffbd774d135	(chrome.dll -devtools_embedder_message_dispatcher.cc:91 )	`anonymous namespace'::ParseAndHandle<bool>
0x00007ffbd774c855	(chrome.dll -devtools_embedder_message_dispatcher.cc:123 )	DispatcherImpl::Dispatch(base::RepeatingCallback<void > const &,std::basic_string<char,std::char_traits<char>,std::allocator<char> > const &,base::ListValue const *)
0x00007ffbd727ff57	(chrome.dll -devtools_ui_bindings.cc:645 )	DevToolsUIBindings::HandleMessageFromDevToolsFrontend(std::basic_string<char,std::char_traits<char>,std::allocator<char> > const &)
0x00007ffbd621a40c	(chrome.dll -devtools_frontend.mojom.cc:356 )	blink::mojom::DevToolsFrontendHostStubDispatch::Accept(blink::mojom::DevToolsFrontendHost *,mojo::Message *)
0x00007ffbd6e72be2	(chrome.dll -ipc_mojo_bootstrap.cc:853 )	IPC::`anonymous namespace'::ChannelAssociatedGroupController::AcceptOnProxyThread
0x00007ffbd6e710c7	(chrome.dll -bind_internal.h:603 )	base::internal::Invoker<base::internal::BindState<void (IPC::(anonymous namespace)::ChannelAssociatedGroupController::*)(mojo::Message),scoped_refptr<IPC::(anonymous namespace)::ChannelAssociatedGroupController>,base::internal::PassedWrapper<mojo::Message> >,void ()>::Run
0x00007ffbd584fe94	(chrome.dll -task_annotator.cc:101 )	base::debug::TaskAnnotator::RunTask(char const *,base::PendingTask *)
0x00007ffbd584f96b	(chrome.dll -message_loop.cc:319 )	base::MessageLoop::RunTask(base::PendingTask *)
0x00007ffbd584f3b7	(chrome.dll -message_loop.cc:373 )	base::MessageLoop::DoWork()
0x00007ffbd5942328	(chrome.dll -message_pump_win.cc:173 )	base::MessagePumpForUI::DoRunLoop()
0x00007ffbd58949f7	(chrome.dll -message_pump_win.cc:56 )	base::MessagePumpWin::Run(base::MessagePump::Delegate *)
0x00007ffbd584ef10	(chrome.dll -run_loop.cc:102 )	base::RunLoop::Run()
0x00007ffbd5bd7ac3	(chrome.dll -chrome_browser_main.cc:2155 )	ChromeBrowserMainParts::MainMessageLoopRun(int *)
0x00007ffbd5bd78c7	(chrome.dll -browser_main_loop.cc:977 )	content::BrowserMainLoop::RunMainMessageLoopParts()
0x00007ffbd5bd7872	(chrome.dll -browser_main_runner_impl.cc:169 )	content::BrowserMainRunnerImpl::Run()
0x00007ffbd63d7782	(chrome.dll -browser_main.cc:51 )	content::BrowserMain(content::MainFunctionParams const &,std::unique_ptr<content::BrowserProcessSubThread,std::default_delete<content::BrowserProcessSubThread> >)
0x00007ffbd691b8c6	(chrome.dll -content_main_runner_impl.cc:620 )	content::RunBrowserProcessMain(content::MainFunctionParams const &,content::ContentMainDelegate *,std::unique_ptr<content::BrowserProcessSubThread,std::default_delete<content::BrowserProcessSubThread> >)
0x00007ffbd5845795	(chrome.dll -content_main_runner_impl.cc:964 )	content::ContentMainRunnerImpl::Run()
0x00007ffbd5835172	(chrome.dll -main.cc:459 )	service_manager::Main(service_manager::MainParams const &)
0x00007ffbd5834a07	(chrome.dll -content_main.cc:19 )	content::ContentMain(content::ContentMainParams const &)
0x00007ffbd5831af1	(chrome.dll -chrome_main.cc:101 )	ChromeMain
0x00007ff6a70c35d5	(chrome.exe -main_dll_loader_win.cc:201 )	MainDllLoader::Launch(HINSTANCE__ *,base::TimeTicks)
0x00007ff6a70c1698	(chrome.exe -chrome_exe_main_win.cc:230 )	wWinMain
0x00007ff6a7193585	(chrome.exe -exe_common.inl:283 )	__scrt_common_main_seh
0x00007ffc19cc1fe3	(KERNEL32.dll + 0x00011fe3 )	
0x00007ffc1adbf060	(ntdll.dll + 0x0006f060 )	RtlUserThreadStart

Adding release blocker label for this issue.Please reduce priority or remove if not the case.

Thank You!

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/e1e8576ba346bf0aba99f860853e835975dffc06

commit e1e8576ba346bf0aba99f860853e835975dffc06
Author: Saman Sami <samans@chromium.org>
Date: Fri Jun 01 18:38:33 2018

Fix crash in DevToolsEyeDropper::AttachToHost

The view can be null when the renderer has crashed. Early out in that
case.

Bug:  847363 
Change-Id: I1f1e4c71a964551d8d329056aeb3670c6ede2167
Reviewed-on: https://chromium-review.googlesource.com/1081883
Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Saman Sami <samans@chromium.org>
Cr-Commit-Position: refs/heads/master@{#563733}
[modify] https://crrev.com/e1e8576ba346bf0aba99f860853e835975dffc06/chrome/browser/devtools/devtools_eye_dropper.cc

I will merge this into M68 after a few days on Canary.

[Auto-generated comment by a script] We noticed that this issue is targeted for M-68; it appears the fix may have landed after branch point, meaning a merge might be required. Please confirm if a merge is required here - if so add Merge-Request-68 label, otherwise remove Merge-TBD label. Thanks.

I would like to merge this CL into M68 because it fixes a browser crash and the fix is perfectly safe.

Approved. BRanch:3440

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/24f6de8e1cef4570bfbd76c75a605278fa9dae8f

commit 24f6de8e1cef4570bfbd76c75a605278fa9dae8f
Author: Saman Sami <samans@chromium.org>
Date: Mon Jun 04 19:46:11 2018

Fix crash in DevToolsEyeDropper::AttachToHost

The view can be null when the renderer has crashed. Early out in that
case.

Bug:  847363 
Change-Id: I1f1e4c71a964551d8d329056aeb3670c6ede2167
Reviewed-on: https://chromium-review.googlesource.com/1081883
Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Saman Sami <samans@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#563733}(cherry picked from commit e1e8576ba346bf0aba99f860853e835975dffc06)
Reviewed-on: https://chromium-review.googlesource.com/1085967
Reviewed-by: Saman Sami <samans@chromium.org>
Cr-Commit-Position: refs/branch-heads/3440@{#157}
Cr-Branched-From: 010ddcfda246975d194964ccf20038ebbdec6084-refs/heads/master@{#561733}
[modify] https://crrev.com/24f6de8e1cef4570bfbd76c75a605278fa9dae8f/chrome/browser/devtools/devtools_eye_dropper.cc

Update : 

Retested above issue in latest Dev build #68.0.3440.15 on Windows(7, 8, 8.1, 10), Mac(10.12.6, 10.13.1, 10.13.6) & Linux (14.04 LTS) OS and the issue is fixed. Browser does not crash after clicking on 'Add background-color' icon in Devtools>>Styles.
Kindly review an attached screen-cast for the reference.

Thank you..!

Deleted: Dev_Behaviour.mp4 732 KB

	Dev_Behaviour.mp4 732 KB View Download

The NextAction date has arrived: 2018-06-05