Properly throw java exceptions from shouldOverrideUrlLoading

base/test/android/java_handler_thread_for_testing.h

+// Copyright 2016 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.
+
+#ifndef BASE_ANDROID_JAVA_HANDLER_THREAD_FOR_TESTING_H_
+#define BASE_ANDROID_JAVA_HANDLER_THREAD_FOR_TESTING_H_
+
+#include "base/android/java_handler_thread.h"
+#include "base/android/java_message_handler_factory.h"
+#include "base/message_loop/message_loop.h"
+#include "base/test/android/test_system_message_handler_link_android.h"
+
+namespace base {
+
+namespace android {
+
+// Factory class for creating a custom Java-side message handler.
+// The implementation of this class creates a test-only message handler, so to
+// avoid including the code of that message handler in production code we use a
+// factory to create it instead of directly creating it from MessagePumpForUI.
+class TestJavaMessageHandlerFactory : public JavaMessageHandlerFactory {
+  base::android::ScopedJavaLocalRef<jobject> CreateMessageHandler(
+      JNIEnv* env,
+      base::MessagePump::Delegate* delegate,
+      MessagePumpForUI* message_pump,
+      WaitableEvent* test_done_event) override;
+};
+
+// Test-version of JavaHandlerThread, we need this class to start and stop the
+// message loop of the new thread in a different way than JavaHandlerThread
+// does.
+// This is partly because we need to create a test-only java-side message
+// handler to back the native message loop, and partly because our tests cause
+// the corresponding message pump to abort which means it won't reach its idle
+// work state and thus can't quit when idle. We here stop the pump more abruptly
+// instead.
+class JavaHandlerThreadForTesting : public JavaHandlerThread {
+ public:
+  JavaHandlerThreadForTesting(const char* name,
+                              base::WaitableEvent* test_done_event);
+  ~JavaHandlerThreadForTesting() override;
+
+  void StartMessageLoop() override;
+  void StopMessageLoop() override;
+
+ private:
+  std::unique_ptr<JavaMessageHandlerFactory> message_handler_factory_;
+  base::WaitableEvent* test_done_event_;
+};
+
+}  // namespace android
+}  // namespace base
+
+#endif  // BASE_ANDROID_JAVA_HANDLER_THREAD_FOR_TESTING_H_