Revert "[base] Use FuzzedDataProvider included in LLVM package."

This reverts commit 20d2671d.

Reason for revert: Causes build failures on iOS bots, see: https://crbug.com/999096

Original change's description:
> [base] Use FuzzedDataProvider included in LLVM package.
> 
> Bug: 991200
> Change-Id: Iee88e3a81057d509e18a2875a3070c5abc17c959
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1774303
> Auto-Submit: Max Moroz <mmoroz@chromium.org>
> Commit-Queue: Lei Zhang <thestig@chromium.org>
> Reviewed-by: Lei Zhang <thestig@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#691207}

TBR=thestig@chromium.org,mmoroz@chromium.org

Change-Id: I044f8863f8fa7e2bb9e70b0f33e73fdd8bfa2a29
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 991200, 999096
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1776043Reviewed-by: Oskar Sundbom <ossu@chromium.org>
Commit-Queue: Oskar Sundbom <ossu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#691575}

base/DEPS

@@ -17,3 +17,10 @@ include_rules = [
   # //base/util can use //base but not vice versa.
   "-util",
 ]
+
+specific_include_rules = {
+  # Dependencies specific for fuzz targets and other fuzzing-related code.
+  ".*fuzz.*": [
+    "+third_party/libFuzzer/src/utils",  # This contains FuzzedDataProvider.
+  ],
+}

base/pickle_fuzzer.cc

@@ -2,10 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include <fuzzer/FuzzedDataProvider.h>
-
 #include "base/macros.h"
 #include "base/pickle.h"
+#include "third_party/libFuzzer/src/utils/FuzzedDataProvider.h"
 
 namespace {
 constexpr int kIterations = 16;

base/test/OWNERS

@@ -13,3 +13,6 @@ per-file BUILD.gn=file://base/test/android/OWNERS
 
 # Linux fontconfig changes
 per-file *fontconfig*=file://base/nix/OWNERS
+
+# FuzzedDataProvider helper class.
+per-file *fuzzed_data_provider*=file://testing/libfuzzer/OWNERS