Add TestBrowserThreadBundle into RenderViewHostTestHarness. Kill some unnecessary real threads.

content/public/test/test_browser_thread_bundle.h

+// Copyright (c) 2013 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.
+
+// TestBrowserThreadBundle is a convenience class for creating a set of
+// TestBrowserThreads in unit tests.  For most tests, it is sufficient to
+// just instantiate the TestBrowserThreadBundle as a member variable.
+//
+// By default, all of the created TestBrowserThreads will be backed by a single
+// shared MessageLoop. If a test truly needs separate threads, it can do
+// so by passing the appropriate combination of RealThreadsMask values during
+// the TestBrowserThreadBundle construction.
+//
+// The TestBrowserThreadBundle will attempt to drain the MessageLoop on
+// destruction. Sometimes a test needs to drain currently enqueued tasks
+// mid-test. Browser tests should call content::RunAllPendingInMessageLoop().
+// Unit tests should use base::RunLoop (e.g., base::RunLoop().RunUntilIdle()).
+// TODO(phajdan.jr): Revise this comment after switch to Aura.
+//
+// Some tests using the IO thread expect a MessageLoopForIO. Passing
+// IO_MAINLOOP will use a MessageLoopForIO for the main MessageLoop.
+// Most of the time, this avoids needing to use a REAL_IO_THREAD.
+
+#ifndef CONTENT_PUBLIC_TEST_TEST_BROWSER_THREAD_TEST_BUNDLE_H_
+#define CONTENT_PUBLIC_TEST_TEST_BROWSER_THREAD_TEST_BUNDLE_H_
+
+#include "base/memory/scoped_ptr.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace base {
+class MessageLoop;
+}  // namespace base
+
+namespace content {
+
+class TestBrowserThread;
+
+class TestBrowserThreadBundle {
+ public:
+  // Used to specify the type of MessageLoop that backs the UI thread, and
+  // which of the named BrowserThreads should be backed by a real
+  // threads. The UI thread is always the main thread in a unit test.
+  enum Options {
+    DEFAULT = 0x00,
+    IO_MAINLOOP = 0x01,
+    REAL_DB_THREAD = 0x02,
+    REAL_WEBKIT_DEPRECATED_THREAD = 0x04,
+    REAL_FILE_THREAD = 0x08,
+    REAL_FILE_USER_BLOCKING_THREAD = 0x10,
+    REAL_PROCESS_LAUNCHER_THREAD = 0x20,
+    REAL_CACHE_THREAD = 0x40,
+    REAL_IO_THREAD = 0x80,
+  };
+
+  TestBrowserThreadBundle();
+  explicit TestBrowserThreadBundle(int options);
+
+  ~TestBrowserThreadBundle();
+
+ private:
+  void Init(int options);
+
+  scoped_ptr<base::MessageLoop> message_loop_;
+  scoped_ptr<TestBrowserThread> ui_thread_;
+  scoped_ptr<TestBrowserThread> db_thread_;
+  scoped_ptr<TestBrowserThread> webkit_deprecated_thread_;
+  scoped_ptr<TestBrowserThread> file_thread_;
+  scoped_ptr<TestBrowserThread> file_user_blocking_thread_;
+  scoped_ptr<TestBrowserThread> process_launcher_thread_;
+  scoped_ptr<TestBrowserThread> cache_thread_;
+  scoped_ptr<TestBrowserThread> io_thread_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestBrowserThreadBundle);
+};
+
+}  // namespace content
+
+#endif /* CONTENT_PUBLIC_TEST_TEST_BROWSER_THREAD_TEST_BUNDLE_H_ */