GWP-ASan: Wire crash handler into crash component

Add the GWP-ASan crash handler hook to the list of user stream data
sources in the Windows crashpad process. The GWP-ASan crash handler
inspects crashes, and if they are related to a GWP-ASan allocation, adds
additional debugging data to the minidump.

CQ-DEPEND=CL:1330283

Bug: 896019
Change-Id: I0b38c60cd46c029200240560fdb714fbd2087f70
Reviewed-on: https://chromium-review.googlesource.com/c/1338324
Commit-Queue: Vlad Tsyrklevich <vtsyrklevich@chromium.org>
Reviewed-by: Mark Mentovai <mark@chromium.org>
Cr-Commit-Position: refs/heads/master@{#611472}

components/crash/content/app/BUILD.gn

@@ -126,6 +126,7 @@ if (is_win) {
     deps = [
       "//base",
       "//components/browser_watcher:crash_stability",
+      "//components/gwp_asan/crash_handler",
       "//third_party/crashpad/crashpad/client",
       "//third_party/crashpad/crashpad/handler",
       "//third_party/crashpad/crashpad/minidump",

components/crash/content/app/DEPS

@@ -2,6 +2,7 @@ include_rules = [
   "+sandbox",
 
   "+components/browser_watcher/stability_report_user_stream_data_source.h",
+  "+components/gwp_asan/crash_handler/crash_handler.h",
   "+content/public/common/content_descriptors.h",
   "+content/public/common/result_codes.h",
   "+third_party/crashpad",

components/crash/content/app/run_as_crashpad_handler_win.cc

@@ -16,6 +16,7 @@
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "components/browser_watcher/stability_report_user_stream_data_source.h"
+#include "components/gwp_asan/crash_handler/crash_handler.h"
 #include "third_party/crashpad/crashpad/client/crashpad_info.h"
 #include "third_party/crashpad/crashpad/client/simple_string_dictionary.h"
 #include "third_party/crashpad/crashpad/handler/handler_main.h"
@@ -83,6 +84,9 @@ int RunAsCrashpadHandler(const base::CommandLine& command_line,
             user_data_dir));
   }
 
+  user_stream_data_sources.push_back(
+      std::make_unique<gwp_asan::UserStreamDataSource>());
+
   return crashpad::HandlerMain(static_cast<int>(storage.size()),
                                argv_as_utf8.get(), &user_stream_data_sources);
 }