Add breakpad component to GN build.

components/breakpad/browser/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.
+
+source_set("browser") {
+  sources = [
+    "crash_dump_manager_android.cc",
+    "crash_dump_manager_android.h",
+  ]
+
+  if (is_linux || is_android) {
+    set_sources_assignment_filter([])
+    # Want this file on both Linux and Android.
+    sources += [
+      "crash_handler_host_linux.cc",
+      "crash_handler_host_linux.h",
+    ]
+  }
+
+  deps = [
+    "//base",
+    "//components/breakpad/app",
+    "//content/public/browser",
+    "//content/public/common",
+  ]
+
+  # This is not in the GYP build but this target includes breakpad client
+  # headers, so add the dependency here.
+  if (is_posix && !is_ios &&
+             (!is_android || !is_android_webview_build)) {
+    deps += [ "//breakpad:client" ]
+  }
+}