Changing SpawnChild to return a struct.

base/BUILD.gn

Index: base/BUILD.gn
diff --git a/base/BUILD.gn b/base/BUILD.gn
index 59b32077fc5036229d87c630a5a331ea6ddf88ad..448d213bf9a533ffcc54812b43be61142cb9fc85 100644
--- a/base/BUILD.gn
+++ b/base/BUILD.gn
@@ -183,6 +183,8 @@ component("base") {
     "android/event_log.h",
     "android/field_trial_list.cc",
     "android/field_trial_list.h",
+    "android/global_object_registry.cc",
+    "android/global_object_registry.h",
     "android/important_file_writer_android.cc",
     "android/important_file_writer_android.h",
     "android/java_exception_reporter.cc",
@@ -215,6 +217,10 @@ component("base") {
     "android/locale_utils.h",
     "android/memory_pressure_listener_android.cc",
     "android/memory_pressure_listener_android.h",
+    "android/parcelable_channel_client.cc",
+    "android/parcelable_channel_client.h",
+    "android/parcelable_channel_server.cc",
+    "android/parcelable_channel_server.h",
     "android/path_service_android.cc",
     "android/path_service_android.h",
     "android/path_utils.cc",
@@ -2404,6 +2410,8 @@ if (is_android) {
       "android/java/src/org/chromium/base/JavaHandlerThread.java",
       "android/java/src/org/chromium/base/LocaleUtils.java",
       "android/java/src/org/chromium/base/MemoryPressureListener.java",
+      "android/java/src/org/chromium/base/ParcelableChannelClient.java",
+      "android/java/src/org/chromium/base/ParcelableChannelServer.java",
       "android/java/src/org/chromium/base/PathService.java",
       "android/java/src/org/chromium/base/PathUtils.java",
       "android/java/src/org/chromium/base/PowerMonitor.java",
@@ -2437,6 +2445,7 @@ if (is_android) {
       ":base_android_java_enums_srcjar",
       ":base_build_config_gen",
       ":base_native_libraries_gen",
+      ":base_java_aidl",
     ]
 
     deps = [
@@ -2466,6 +2475,8 @@ if (is_android) {
       "android/java/src/org/chromium/base/FieldTrialList.java",
       "android/java/src/org/chromium/base/FileUtils.java",
       "android/java/src/org/chromium/base/ImportantFileWriterAndroid.java",
+      "android/java/src/org/chromium/base/ParcelableChannelClient.java",
+      "android/java/src/org/chromium/base/ParcelableChannelServer.java",
       "android/java/src/org/chromium/base/JNIUtils.java",
       "android/java/src/org/chromium/base/JavaExceptionReporter.java",
       "android/java/src/org/chromium/base/JavaHandlerThread.java",
@@ -2475,6 +2486,7 @@ if (is_android) {
       "android/java/src/org/chromium/base/NonThreadSafe.java",
       "android/java/src/org/chromium/base/ObserverList.java",
       "android/java/src/org/chromium/base/PackageUtils.java",
+      "android/java/src/org/chromium/base/ParcelableWrapper.java",
       "android/java/src/org/chromium/base/PathService.java",
       "android/java/src/org/chromium/base/PathUtils.java",
       "android/java/src/org/chromium/base/PerfTraceEvent.java",
@@ -2653,6 +2665,13 @@ if (is_android) {
       "test/android/java/src/org/chromium/base/TestSystemMessageHandler.java",
     ]
   }
+
+  android_aidl("base_java_aidl") {
+    import_include = [ "android/java/src" ]
+    sources = [
+      "android/java/src/org/chromium/base/IParcelableChannel.aidl",
+    ]
+  }
 }
 
 fuzzer_test("base_json_correctness_fuzzer") {