cleanup one test and workingset view extensibility
mutable file object for wsv item class
fix comment
rework classes array
allow refresh to update the class list without rebuilding the entire view
update doc to support jQuery for IconProvider
update comment
update comment again
remove unused var in test
- filter only [Extension] console output for the ExtensionLoader tests
merge with master
rtc:nits
Merge branch 'master' into jeff/wsv-extensibility
Display error messages on rename.

Fix for #9230.
Allows you to create a file/folder with the default name.

Fix for #9216
Clean up after trying to create an invalid file.

Fix for #9232.
Ensure that `this.state.clickTime` does not produce a null error.

As seen in comments of #9264.
Check for left click on directories and files.

Fix for #9241
- guard against null and non string arguments passed to console.error
Fix a second infinite loop in CSSUtils.findSelectorAtDocumentPos(), caused
by cleanups in the fix for the earlier infinite loop bug. To keep loop
exit condition more precisely in sync with TokenUtils's logic for when to
stop advancing, create new TokenUtils methods for checking if at a stopping
point.