Console contains "Unable to stat changed path" warnings from inside .git folder after big checkouts

[peterflynn]

I've seen this several times and it was also reported in #6799.

1. Open a project in Brackets
2. Using git on the command line, switch between two widely different branches in the project
3. Look at Brackets console log

Result:
A dozen or so warnings of the form "Unable to stat changed path: .git... NotFound"

Expected:
We're supposed to ignore churn inside the .git folder, so this is confusing and perhaps unnecessarily scary-looking.

As best I can tell it's actually harmless though: AppShellFileSystem._enqueueChange() fails to stat and then sends the change along to FileSystem anyway, where it is promptly dropped on the floor since that folder is filtered out by the watch-root's filter.

[peterflynn]

We could fix this by passing the filter down into the impl so it can ignore paths like this. This should also increase efficiency since we're not wasting time running stat() calls (failed or otherwise) for churn inside .git. But we'd need to make sure it doesn't change the semantics of what happens when the user explicitly opens a file that's been filtered out.

[njx]

Low pri to @peterflynn

[peterflynn]

PR #7332 eliminates the warning entirely for now. I view that as an interim fix since, ideally:

1. We wouldn't waste time trying to stat() churn inside folders like .git (which btw can churn quite a bit during a big fetch/pull/commit/etc.).
2. We still would warn if we failed to stat() something that was not filtered out of the watch root -- since failing to stat() means we drop the change notification on the floor, it's actually a fairly significant error in the not-filtered case.