Unable to provide narrow bisect as getting all good builds in tool bisect.Hence providing Change Log info.
Change Log info : 
https://chromium.googlesource.com/chromium/src/+log/56.0.2897.0..56.0.2899.0?pretty=fuller&n=10000

Suspecting: 426824 from CL

@jgruber : Could you please help to reassign if your change is not the cause for this change.

This is strange: Tried to repro it on my Mac and the repro worked the first time. Afterwards it I couldn't repro it anymore. The whole reloading going on looks strange though.

The repro video shows some Finch experiments going on. On the as expected video no experiments are running. Could you please paste the content of all the "variations" from about:version from your installation that repros the problem?

In repro case, what is shown in the console?

Haven't managed to repro at all on Linux so far.

With response to comment #3:
Please refer the attached screenshot of about:version for your reference.

Deleted: Actual.png 729 KB

	Actual.png 729 KB View Download

Deleted: Expected.png 983 KB

	Expected.png 983 KB View Download

Thanks, could you please copy and paste the hashes into the bug as text? We need to convert them into human readable names and a picture cannot be taken as an input.

With response to comment #6 :
Variations	6a89113b-a7aa8ed
68ebfce2-ca7d8d80
16e0dd70-3f4a17df
31101bd6-f23d1dea
da89714-4ad60575
241fff6c-ca7d8d80
1e528f0f-ca7d8d80
e197bfc9-ca7d8d80
8364a5c2-ca7d8d80
7c1bc906-f55a7974
5829eceb-ca7d8d80
1c752ce9-1410f10
ba3f87da-d0f2c564
f049a919-3f4a17df
5ca89f9-3f4a17df
76b48ab8-a2567007
31362330-3f4a17df
c70841c8-a2567007
f15c1c09-ca7d8d80
9e201a2b-f23d1dea
5274eb09-3f4a17df
684d1cdf-f23d1dea
bcc907f7-ef01e3f3
9773d3bd-3f4a17df
a4566d9e-3d47f4f4
2e109477-e2e291f1
9e5c75f1-d357b5f9
6b121ae7-df25e660
5139837c-3f4a17df
7f8176d9-f23d1dea
f5dd6118-2f5721af
f79cb77b-3d47f4f4
b7786474-d93a0620
23a898eb-ca7d8d80
74df3f1-3f4a17df
7382e39a-3f4a17df
4ea303a6-408058f9
7a3692af-94cb2461
f2e050c6-bc6856d9
fe9bec35-80f9a33e
9736de91-3f4a17df
dbffab5d-ca7d8d80
de03e059-f23d1dea
64005e71-fb487281
ca314179-ea08a3f2
69bf80fa-3f4a17df
c5073fab-3f4a17df
867c4c68-3f4a17df
b2f0086-35a81a97
d747916f-f23d1dea
76923fa8-e0ae2f34
477f6800-bbfbea97
3ac60855-486e2a9c
f296190c-da18db08
4442aae2-75cb33fc
ed1d377-e1cc0f14
75f0f0a0-d7f6b13c
e2b18481-6e597ede
e7e71889-e1cc0f14
fe05be5f-486e2a9c
61b920c1-1410f10
828a5926-aac10f8f

Finally reproduced this on a Mac.

about:version
-------------

Google Chrome	56.0.2899.0 (Official Build) canary (64-bit)
Revision	bb7071018e1fd8bf223b8ffff660883b7d17278d-refs/heads/master@{#426989}
OS	Mac OS X 
JavaScript	V8 5.6.134
Flash	23.0.0.198
User Agent	Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2899.0 Safari/537.36

Variations
----------

6a89113b-a7aa8ed
68ebfce2-34df6b5c
16e0dd70-3f4a17df
31101bd6-3f4a17df
da89714-4ad60575
241fff6c-ca7d8d80
1e528f0f-3b7f37f3
e197bfc9-ca7d8d80
8364a5c2-ca7d8d80
7c1bc906-ff96eb58
5829eceb-ca7d8d80
1c752ce9-1410f10
ba3f87da-1410f10
f049a919-3f4a17df
5ca89f9-f23d1dea
76b48ab8-a2567007
31362330-3f4a17df
c70841c8-a2567007
f15c1c09-ca7d8d80
9e201a2b-3f4a17df
5274eb09-3f4a17df
f11437-f23d1dea
bcc907f7-3f4a17df
9773d3bd-f23d1dea
a4566d9e-3d47f4f4
2e109477-e2e291f1
9e5c75f1-cbe0f36
6b121ae7-9f192e4b
5139837c-3f4a17df
7f8176d9-3f4a17df
f5dd6118-2f5721af
f79cb77b-3d47f4f4
b7786474-d93a0620
23a898eb-e0e2610f
7382e39a-3f4a17df
4ea303a6-121b72d9
7a3692af-99f3d462
f2e050c6-94cb2461
fe9bec35-186f5907
9736de91-3f4a17df
dbffab5d-f23d1dea
64005e71-80deee2a
ca314179-ea08a3f2
69bf80fa-3f4a17df
c5073fab-3f4a17df
867c4c68-3f4a17df
b2f0086-f23d1dea
d747916f-d747916f
76923fa8-9cf3205c
3ac60855-486e2a9c
f296190c-cc017729
4442aae2-e1cc0f14
ed1d377-e1cc0f14
75f0f0a0-6bdfffe7
e2b18481-a5822863
e7e71889-e1cc0f14
fe05be5f-4001c964
61b920c1-48c6f5be
828a5926-aac10f8f

Devtools console output
-----------------------

The output is not consistent unfortunately. I saw this once:

Uncaught TypeError: Cannot read property 'aa' of undefined
    at EV.ia (rs=AGyH-FuHiLBnhd2l3HU9KLLwuusDGFfaZQ:1955)
    at Gp (rs=AGyH-FuHiLBnhd2l3HU9KLLwuusDGFfaZQ:780)
    at uy.g.dispatchEvent (rs=AGyH-FuHiLBnhd2l3HU9KLLwuusDGFfaZQ:779)
    at uy.ra (rs=AGyH-FuHiLBnhd2l3HU9KLLwuusDGFfaZQ:961)
    at uy.<anonymous> (rs=AGyH-FuHiLBnhd2l3HU9KLLwuusDGFfaZQ:1949)
    at wV.<anonymous> (rs=AGyH-FuHiLBnhd2l3HU9KLLwuusDGFfaZQ:1949)
    at lO.aa (rs=AGyH-FuHiLBnhd2l3HU9KLLwuusDGFfaZQ:1535)
    at Function.eO (rs=AGyH-FuHiLBnhd2l3HU9KLLwuusDGFfaZQ:1518)
    at Jp (rs=AGyH-FuHiLBnhd2l3HU9KLLwuusDGFfaZQ:774)
    at zp (rs=AGyH-FuHiLBnhd2l3HU9KLLwuusDGFfaZQ:775)

This error looks very similar to crbug.com/656959, which also has similar symptoms. However, the sheets document also fails to load when the error is not thrown.

Repro instructions
------------------

1. With the chrome version specified above,
2. Open gmail.com.
3. Using the search box, find a sheets document and open it directly from the search box.
4. The document title shows up, but the remaining document fails to load. 

Might be important: the repro happened on a non-corp device, and on a simple empty new sheets document.

Able to reproduce this issue on corp device (Macbook Pro Retina , 10.11.6), #56.0.2899.0, followed the steps mentioned in c#8

providing console output:
1266047508-ritz_waffle_i18n_gvizcharts.js:1477 [Report Only] Refused to load plugin data from '' because it violates the following Content Security Policy directive: "object-src 'none'".

about:version:
---------------

Google Chrome	56.0.2899.0 (Official Build) dev (64-bit)
Revision	bb7071018e1fd8bf223b8ffff660883b7d17278d-refs/heads/master@{#426989}
OS	Mac OS X 
JavaScript	V8 5.6.134
Flash	23.0.0.198
User Agent	Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2899.0 Safari/537.36
Command Line	/Applications/Google Chrome.app/Contents/MacOS/Google Chrome -psn_0_10955378 --flag-switches-begin --flag-switches-end
Executable Path	/Applications/Google Chrome.app/Contents/MacOS/Google Chrome
Profile Path	/Users/nyerramilli/Library/Application Support/Google/Chrome/Default

I am able to reproduce this issue consistently on both Corp & Non-corp chrome builds, however unable to reproduce this on Chromium builds using "bisect-builds.py" script.

The above console o/p (c#11) exists even for working chrome, so i do not think we really draw any conclusion out of it.

This seems to be a blocker for tomorrow's M56 Dev release and would be really great if we can land the fix/revert ASAP.

Thank you!

Finally, per revision bisect worked fine and below is the suspected change.

https://chromium.googlesource.com/chromium/src/+/7c3d7bbd510eda2bcfb971f6d166da26bcfe4222, which has already been reverted.

Thank you!

Thanks guys!

Tested the issue on Mac 10.11.6 using chrome version 56.0.2900.0.Able to open and view the excel sheets without any issue.
Could any one please update the status accordingly.

Thanks,

As stated, it is not reliably reproducing for everybody. lfg@ PTAL.

After the above revert, i am not seeing this issue on Latest Canary#56.0.2900.0 for Mac OS X 10.11.6.