Rename buildflag_headers for consistency

This updates printing.

Targets go from foo_features to foo_buildflags
And similarly the header now has buildflags in the name.

BUG=814485
TEST=covered by build

Change-Id: I455c5638ef9bcd98f669fc7117b4699a34292fd0
Reviewed-on: https://chromium-review.googlesource.com/988132
Reviewed-by: Daniel Cheng <[email protected]>
Commit-Queue: Scott Violet <[email protected]>
Cr-Commit-Position: refs/heads/master@{#547228}
diff --git a/printing/printing_context_win.cc b/printing/printing_context_win.cc
index ff0d7054..6beedaa 100644
--- a/printing/printing_context_win.cc
+++ b/printing/printing_context_win.cc
@@ -15,7 +15,7 @@
 #include "base/strings/utf_string_conversions.h"
 #include "printing/backend/print_backend.h"
 #include "printing/backend/win_helper.h"
-#include "printing/features/features.h"
+#include "printing/buildflags/buildflags.h"
 #include "printing/print_settings_initializer_win.h"
 #include "printing/printed_document.h"
 #include "printing/printing_context_system_dialog_win.h"