Running git cl format generated the following code excerpt: 

...
traits_headers =
    [ "//content/common/cache_storage/cache_storage_mojom_traits.h" ]
sources = [
  "//content/common/cache_storage/cache_storage_mojom_traits.cc",
]
deps = [
  "//mojo/public/cpp/bindings",
]
...

The handle of trailing comma and opening/closing brackets seems inconsistent between traits_headers and sources/deps.

I would expect the following output:
...
traits_headers = [ 
  "//content/common/cache_storage/cache_storage_mojom_traits.h",
]
sources = [
  "//content/common/cache_storage/cache_storage_mojom_traits.cc",
]
deps = [
  "//mojo/public/cpp/bindings",
]
...

OR: 
...
traits_headers = 
    [ "//content/common/cache_storage/cache_storage_mojom_traits.h" ]
sources =
    [ "//content/common/cache_storage/cache_storage_mojom_traits.cc" ]
deps = [ "//mojo/public/cpp/bindings" ]
...