A simple, practically zero cost fallback crash handler for Crashpad handler process.

components/crash/content/app/BUILD.gn

 # Copyright 2014 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.
 
 assert(!is_ios)
 if (is_android) {
   import("//build/config/android/config.gni")
 }
 
 static_library("lib") {
@@ skipping 48 matching lines @@
   if (is_win) {
     deps += [ "//third_party/crashpad/crashpad/handler:handler_lib" ]
   }
 }
 
 if (is_win) {
   static_library("run_as_crashpad_handler") {
     sources = [
       "crash_switches.cc",
       "crash_switches.h",
+      "fallback_crash_handler_launcher_win.cc",
+      "fallback_crash_handler_launcher_win.h",
+
+      # TODO(siggi): Maybe this wants to be a separate target, as it requires
+      #    the crashpad client as a dependency?
+      "fallback_crash_handler_win.cc",
+      "fallback_crash_handler_win.h",
       "run_as_crashpad_handler_win.cc",
       "run_as_crashpad_handler_win.h",
     ]
 
     deps = [
       "//base",
+      "//third_party/crashpad/crashpad/client",
       "//third_party/crashpad/crashpad/handler:handler_lib",
+      "//third_party/crashpad/crashpad/minidump",
     ]
   }
 }
 
 # TODO(mark): https://crbug.com/466890: merge this target with
 # crash_component.
 #
 # This is a temporary base target that is depended on by both
 # crash_component and crash_component_breakpad_mac_to_be_deleted. It
 # provides everything common to both of those targets. For a short period,
@@ skipping 120 matching lines @@
     deps = [
       "//base",
     ]
   }
 }
 
 source_set("unit_tests") {
   testonly = true
   sources = [
     "crash_keys_win_unittest.cc",
+    "fallback_crash_handler_launcher_win_unittest.cc",
+    "fallback_crash_handler_win_unittest.cc",
   ]
   deps = [
     ":lib",
     "//base",
+    "//base/test:test_support",
     "//testing/gmock",
     "//testing/gtest",
+    "//third_party/crashpad/crashpad/compat",
+    "//third_party/crashpad/crashpad/snapshot:snapshot",
+    "//third_party/crashpad/crashpad/util",
   ]
 
   if (is_win) {
-    deps += [ "//breakpad:client" ]
+    deps += [
+      ":run_as_crashpad_handler",
+      "//breakpad:client",
+      "//third_party/crashpad/crashpad/client",
+    ]
   }
 }