Same issue here. Starting Chrome Canary leads to an immediate hang and requires a force close.

I backed up my Default folder in Application Support/Chrome Canary/ and manually brought things back one by one until the application no longer launched again. 

For me the Local State file caused the issue again. Once it was removed Chrome launched fine however I had to reset any flags.

Chrome Version: 51.0.2702.0
OS Version: 10.11.5 Beta (15F18b)

Thanks a lot - deleting the 'Local State' file resolved the issue for me as well.

I have the same issue, since the update this morning. I'm on Mac. 
I'm still not able to delete the local state file, trying to get that done.

I confirm that deleting Local State in '~/Library/Application Support/Google/Chrome Canary' enabled it to launch.

The web UI screens are still in Times, though...

I'm not seeing this issue. If you are, when Chrome is hung, can you please open Activity Monitor, find the hung Google Chrome Canary process, and get a Sample? Attach the resulting file here and we can take a look.

(FWIW the WebUI bug is  issue 601051 . A fix for it landed but it missed the canary branch today.)

I had the same problem. By removing the Local State, it works again. When I restore the Local State file it hangs again. I made a sample and I've included my Local State file, so you can see what was wrong

Deleted: Local State 63.7 KB

Local State 63.7 KB View Download

Deleted: Sample of Google Chrome.txt 58.6 KB

Sample of Google Chrome.txt 58.6 KB View Download

I'm using 51.0.2702.2 canary (64-bit).
I've minimized the difference of Local State files, and attached them.

Deleted: Local State.hang 29.2 KB

Local State.hang 29.2 KB Download

Deleted: Local State.ok 29.2 KB

Local State.ok 29.2 KB Download

Thanks. Looks like the main thread is blocked on a lock.

    2735 Thread_1696064   DispatchQueue_1: com.apple.main-thread  (serial)
    + 2735 start  (in Google Chrome Canary)  load address 0x101d0a000 + 0xb24  []
    +   2735 main  (in Google Chrome Canary) + 530  [chrome_exe_main_mac.c:91]
    +     2735 ChromeMain  (in Google Chrome Framework) + 66  [chrome_main.cc:84]
    +       2735 content::ContentMain(content::ContentMainParams const&)  (in Google Chrome Framework)  load address 0x101f71000 + 0x523ae6  [content_main.cc:19]
    +         2735 content::ContentMainRunnerImpl::Run()  (in Google Chrome Framework)  load address 0x101f71000 + 0x5246e4  [content_main_runner.cc:741]
    +           2735 content::BrowserMain(content::MainFunctionParams const&)  (in Google Chrome Framework)  load address 0x101f71000 + 0x38c1c05  [browser_main.cc:41]
    +             2735 content::BrowserMainRunnerImpl::Initialize(content::MainFunctionParams const&)  (in Google Chrome Framework)  load address 0x101f71000 + 0x38c8315  [memory:2729]
    +               2735 content::BrowserMainLoop::CreateStartupTasks()  (in Google Chrome Framework)  load address 0x101f71000 + 0x38c43c4  [browser_main_loop.cc:801]
    +                 2735 content::StartupTaskRunner::RunAllTasksNow()  (in Google Chrome Framework)  load address 0x101f71000 + 0x3ba4870  [callback.h:397]
    +                   2735 content::BrowserMainLoop::PreCreateThreads()  (in Google Chrome Framework)  load address 0x101f71000 + 0x38c3e2f  [browser_main_loop.cc:695]
    +                     2735 ChromeBrowserMainParts::PreCreateThreads()  (in Google Chrome Framework)  load address 0x101f71000 + 0x977ec  [chrome_browser_main.cc:867]
    +                       2735 ChromeBrowserMainParts::PreCreateThreadsImpl()  (in Google Chrome Framework)  load address 0x101f71000 + 0x98776  [memory:2729]
    +                         2735 ChromeBrowserMainParts::SetupMetricsAndFieldTrials()  (in Google Chrome Framework)  load address 0x101f71000 + 0x96dea  [chrome_browser_main.cc:736]
    +                           2735 ChromeBrowserFieldTrials::SetupFieldTrials()  (in Google Chrome Framework)  load address 0x101f71000 + 0x9659d  [chrome_browser_field_trials.cc:62]
    +                             2735 base::PersistentMemoryAllocator::CreateTrackingHistograms(base::BasicStringPiece<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > >)  (in Google Chrome Framework)  load address 0x101f71000 + 0x596c3c  [persistent_memory_allocator.cc:388]
    +                               2735 <name omitted>  (in Google Chrome Framework)  load address 0x101f71000 + 0x591040  [histogram.cc:244]
    +                                 2735 base::Histogram::Factory::Build()  (in Google Chrome Framework)  load address 0x101f71000 + 0x590e6a  [histogram.cc:150]
    +                                   2735 base::StatisticsRecorder::FindHistogram(base::BasicStringPiece<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > >)  (in Google Chrome Framework)  load address 0x101f71000 + 0x599d9d  [statistics_recorder.cc:301]
    +                                     2735 base::GlobalHistogramAllocator::ImportHistogramsToStatisticsRecorder()  (in Google Chrome Framework)  load address 0x101f71000 + 0x596414  [memory:2737]
    +                                       2735 base::PersistentHistogramAllocator::GetHistogram(unsigned int)  (in Google Chrome Framework)  load address 0x101f71000 + 0x595842  [persistent_histogram_allocator.cc:331]
    +                                         2735 base::PersistentHistogramAllocator::CreateHistogram(base::PersistentHistogramAllocator::PersistentHistogramData*)  (in Google Chrome Framework)  load address 0x101f71000 + 0x595b3d  [persistent_histogram_allocator.cc:243]
    +                                           2735 base::StatisticsRecorder::RegisterOrDeleteDuplicateRanges(base::BucketRanges const*)  (in Google Chrome Framework)  load address 0x101f71000 + 0x5993d5  [statistics_recorder.cc:171]
    +                                             2735 _pthread_mutex_lock_wait  (in libsystem_pthread.dylib) + 89  [0x7fff88689e4a]
    +                                               2735 __psynch_mutexwait  (in libsystem_kernel.dylib) + 10  [0x7fff8540ede6]
    2735 Thread_1696099   DispatchQueue_2: com.apple.libdispatch-manager  (serial)

Brian, can you check if this is related to your changes?

Yes.  Fix is already here:
https://codereview.chromium.org/1872713002/

CL to disable metrics for a while is here:
https://critique.corp.google.com/#review/119340917

Disable "persistent" metrics, I mean.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2f153f83f1d6fcfb4b0b8dae5a6b12dbc6544d6b

commit 2f153f83f1d6fcfb4b0b8dae5a6b12dbc6544d6b
Author: bcwhite <bcwhite@chromium.org>
Date: Fri Apr 08 16:57:56 2016

Remove unnecessary lock that causes reentry.

The StatisticsRecorder is acquiring a lock before
calling Import but the import calls back to the SR
which again tries to acquire the lock... and crashes.

The lock isn't necessary with the new persistent
iterator (which is lock-free) so move the Import
call outside of the locking.

BUG= 601457 

Review URL: https://codereview.chromium.org/1872713002

Cr-Commit-Position: refs/heads/master@{#386102}

[modify] https://crrev.com/2f153f83f1d6fcfb4b0b8dae5a6b12dbc6544d6b/base/metrics/persistent_histogram_allocator.cc
[modify] https://crrev.com/2f153f83f1d6fcfb4b0b8dae5a6b12dbc6544d6b/base/metrics/statistics_recorder.cc

Fix will be in v51.0.2704

i have removed local state as directed but canary continues to not load anything with no settings or functions loading or being operable

 Issue 601896  has been merged into this issue.