Revert of Add PDFium build_overrides

pdf/pdfium/fuzzers/BUILD.gn

 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # PDFium fuzzers.
 
-import("//build_overrides/pdfium.gni")
+import("//third_party/pdfium/pdfium.gni")
 import("//testing/test.gni")
 import("//testing/libfuzzer/fuzzer_test.gni")
 
 group("fuzzers") {
 }
 
 fuzzer_test("pdfium_fuzzer") {
   sources = [
     "pdfium_fuzzer.cc",
   ]
@@ skipping 27 matching lines @@
   }
 
   fuzzer_test("pdf_xml_fuzzer") {
     sources = []
     deps = [
       "//third_party/pdfium/testing/libfuzzer:pdf_xml_fuzzer",
     ]
     dict = "dicts/pdf_xml.dict"
   }
 }