[Blimp] Adds blimp engine browser test framework and LoadUrl test.

blimp/test/browser_tests/blimp_test_launcher.cc

+// 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.
+
+#include <memory>
+
+#include "base/bind.h"
+#include "base/macros.h"
+#include "base/sys_info.h"
+#include "blimp/engine/app/blimp_content_main_delegate.h"
+#include "content/public/test/content_test_suite_base.h"
+#include "content/public/test/test_launcher.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace blimp {
+namespace {
+

[Kevin M, 2016/05/05 20:28:51]

Create a TestBlimpContentMainDelegate, which subclasses BlimpContentMainDelegate
and exposes a static instance getter?

[haibinlu, 2016/05/05 22:41:36]

Done.

+class BlimpTestLauncherDelegate : public content::TestLauncherDelegate {
+ public:
+  BlimpTestLauncherDelegate() {}
+  ~BlimpTestLauncherDelegate() override {}
+
+  // content::TestLauncherDelegate implementation.
+  int RunTestSuite(int argc, char** argv) override {
+    return base::TestSuite(argc, argv).Run();
+  }
+
+  bool AdjustChildProcessCommandLine(
+      base::CommandLine* command_line,
+      const base::FilePath& temp_data_dir) override {
+    return true;
+  }
+
+ protected:
+  content::ContentMainDelegate* CreateContentMainDelegate() override {

[Kevin M, 2016/05/05 20:28:52]

Why is this protected and other overrides public?

[haibinlu, 2016/05/05 22:41:36]

moved it to public.

+    return new engine::BlimpContentMainDelegate();
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(BlimpTestLauncherDelegate);
+};
+
+}  // namespace
+}  // namespace blimp
+
+int main(int argc, char** argv) {
+  int default_jobs = std::max(1, base::SysInfo::NumberOfProcessors() / 2);
+  blimp::BlimpTestLauncherDelegate launcher_delegate;
+  return LaunchTests(&launcher_delegate, default_jobs, argc, argv);
+}