Reland "Add GWP-ASan hook to macOS crashpad handler"

This is a reland of dcea6896 once the
headless_browsertests issue in https://crbug.com/929873 has been fixed.

CQ-DEPEND=CL:1460068

Original change's description:
> Add GWP-ASan hook to macOS crashpad handler
>
> Add the GWP-ASan UserStreamDataSource to the macOS crashpad handler.
> The GWP-ASan hook determines when an exception is related to GWP-ASan
> and reports additional debug information.
>
> Bug: 912286
> Change-Id: I1cd0227ca8aade1bd17e25b83832cdb8f3e58d5e
> Reviewed-on: https://chromium-review.googlesource.com/c/1457461
> Reviewed-by: Mark Mentovai <mark@chromium.org>
> Commit-Queue: Vlad Tsyrklevich <vtsyrklevich@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#629881}

Bug: 912286
Change-Id: I9cac247b9e9b81c97f16da74dc95f21de6f9d6e6
Reviewed-on: https://chromium-review.googlesource.com/c/1460120Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Vlad Tsyrklevich <vtsyrklevich@chromium.org>
Cr-Commit-Position: refs/heads/master@{#630584}

components/crash/content/app/BUILD.gn

@@ -198,6 +198,7 @@ if (is_mac) {
     ]
 
     deps = [
+      "//components/gwp_asan/crash_handler",
       "//third_party/crashpad/crashpad/handler:handler",
     ]
 

components/crash/content/app/chrome_crashpad_handler.cc

@@ -2,8 +2,16 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include <memory>
+
+#include "components/gwp_asan/crash_handler/crash_handler.h"
 #include "third_party/crashpad/crashpad/handler/handler_main.h"
+#include "third_party/crashpad/crashpad/handler/user_stream_data_source.h"
 
 int main(int argc, char* argv[]) {
-  return crashpad::HandlerMain(argc, argv, nullptr);
+  crashpad::UserStreamDataSources user_stream_data_sources;
+  user_stream_data_sources.push_back(
+      std::make_unique<gwp_asan::UserStreamDataSource>());
+
+  return crashpad::HandlerMain(argc, argv, &user_stream_data_sources);
 }