buffet: Remove 'chromeos' namespace and move everything to buffet NS

As discussed, moved all the classes out of chromeos namespace into
'buffet.

Also fixed a number of cpplint's warnings.

BUG=None
TEST=Everything still compiles and unit tests succeed.

Change-Id: Ide864acb2504627404966727f66d353af60e531d
Reviewed-on: https://chromium-review.googlesource.com/198971
Reviewed-by: Christopher Wiley <wiley@chromium.org>
Commit-Queue: Alex Vakulenko <avakulenko@chromium.org>
Tested-by: Alex Vakulenko <avakulenko@chromium.org>
diff --git a/buffet/error.h b/buffet/error.h
index 97c48ee..2f5ba66 100644
--- a/buffet/error.h
+++ b/buffet/error.h
@@ -10,7 +10,7 @@
 
 #include <base/basictypes.h>
 
-namespace chromeos {
+namespace buffet {
 
 class Error;  // Forward declaration.
 
@@ -66,6 +66,6 @@
   DISALLOW_COPY_AND_ASSIGN(Error);
 };
 
-}  // namespace chromeos
+}  // namespace buffet
 
 #endif  // BUFFET_ERROR_H_