Remove fx_bmp.cpp.

It does not contain anything useful that's not already in fx_bmp.h.

Change-Id: Ideea208ae868352a34b30d0d6b82e337575d6374
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/56091
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>

core/fxcodec/BUILD.gn

diff --git a/core/fxcodec/BUILD.gn b/core/fxcodec/BUILD.gn
index 0954de7..0ebadc5 100644
--- a/core/fxcodec/BUILD.gn
+++ b/core/fxcodec/BUILD.gn
@@ -92,7 +92,6 @@
         "bmp/cfx_bmpcontext.h",
         "bmp/cfx_bmpdecompressor.cpp",
         "bmp/cfx_bmpdecompressor.h",
-        "bmp/fx_bmp.cpp",
         "bmp/fx_bmp.h",
         "codec/bmpmodule.cpp",
         "codec/bmpmodule.h",

core/fxcodec/bmp/fx_bmp.cpp

diff --git a/core/fxcodec/bmp/fx_bmp.cpp b/core/fxcodec/bmp/fx_bmp.cpp
deleted file mode 100644
index aca456f..0000000
--- a/core/fxcodec/bmp/fx_bmp.cpp
+++ /dev/null
@@ -1,11 +0,0 @@
-// Copyright 2014 PDFium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
-
-#include "core/fxcodec/bmp/fx_bmp.h"
-
-static_assert(sizeof(BmpFileHeader) == 14,
-              "BmpFileHeader should have a size of 14");
-