Chrome Version: 51.0.2704.22 (Official Build) 92f512ccc621485aa1516c710d65cc6a1990c205-refs/branch-heads/2704@{#157} (64-bit)
OS:Mac OS X 10.10.5, OS X 10.11.4, Mac Retina 10.11.4

What steps will reproduce the problem?
1.Launch chrome and navigate to chrome://settings/content , click on "let me choose when to run.." option under Plugin section.
2.Navigate to vudu.com click on any video such that plugin block bubble appears in omnibox.
3.Manually crash page via chrome://kill, click on bubble select 'always allow plugins' and click on 'manage plugin blocking' button 
4.Observe the entry in chrome://settings/contentExceptions#plugins

Actual: Blank plugin exception entry is created in chrome://settings/contentExceptions#plugins after clicking on 'always allow plugins' option (i.e after step 3&4)

Expected: Blank plugin exception should not be created in chrome://settings/contentExceptions#plugins after clicking on 'always allow plugins' option.

This is a regression broken in 'M45' and below is manual regression range
Good Build: 45.0.2454.6 
Bad Build:  45.0.2454.46

CL:
https://chromium.googlesource.com/chromium/src/+log/45.0.2454.6..45.0.2454.46?pretty=fuller&n=10000
(Unable to narrow down the range via tool since getting same revision between this range)

Suspecting: 338390 ?
Kindly help to re-assign, if your changes are not cause for this issue.

Note: Issue not seen on Windows & Linux OS.
 

Deleted: Actual_plugins.mov 7.9 MB

Actual_plugins.mov 7.9 MB Download