Revert of Allow overriding GN build flags (patchset #2 id:20001 of https://codereview.chromium.org/1923333002/ )

Reason for revert:
Blocking the roll

Original issue's description:
> Allow overriding GN build flags
>
> In order to enable XFA from GN builds we need to be able to override
> pdf_enable_xfa. To do this a build_overrides/pdfium.gni file needs to be created
> in Chrome. To use that, we have to create a build_overrides/pdfium.gni file
> in PDFium that just uses the default values.
>
> BUG=chromium:62400
>
> Committed: https://pdfium.googlesource.com/pdfium/+/1ae572e7e35b52ce4897d1715c005a1b0f79526a

TBR=thakis@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=chromium:62400

Review-Url: https://codereview.chromium.org/1941563002

1 files changed, 1 insertions, 1 deletions

diff --git a/BUILD.gn b/BUILD.gn
index 86e0da32f7..8a96f21f46 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -3,8 +3,8 @@
 # found in the LICENSE file.
 
 import("//build_overrides/v8.gni")
-import("//build_overrides/pdfium.gni")
 import("//testing/test.gni")
+import("pdfium.gni")
 
 config("pdfium_config") {
   cflags = []