Add regression test for bug 7900 and necessary infrastructure....

chrome/app/chrome_main_uitest.cc

Index: chrome/app/chrome_main_uitest.cc
===================================================================
--- chrome/app/chrome_main_uitest.cc	(revision 11106)
+++ chrome/app/chrome_main_uitest.cc	(working copy)
@@ -2,9 +2,13 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "chrome/common/chrome_constants.h"
 #include "chrome/test/ui/ui_test.h"
 
+#include "base/command_line.h"
+#include "base/file_path.h"
+#include "base/file_util.h"
+#include "net/base/net_util.h"
+
 typedef UITest ChromeMainTest;
 
 // Launch the app, then close the app.
@@ -44,3 +48,20 @@
   ASSERT_EQ(2, window_count);
 }
 
+TEST_F(ChromeMainTest, ReuseBrowserInstanceWhenOpeningFile) {
+  include_testing_id_ = false;
+  use_existing_browser_ = true;
+
+  std::wstring test_file = test_data_directory_;
+  file_util::AppendToPath(&test_file, L"empty.html");
+
+  CommandLine command_line(L"");
+  command_line.AppendLooseValue(test_file);
+
+  LaunchBrowser(command_line, false);
+
+  FilePath test_file_path(FilePath::FromWStringHack(test_file));
+
+  ASSERT_TRUE(automation()->WaitForURLDisplayed(
+      net::FilePathToFileURL(test_file_path), action_timeout_ms()));

[Nicolas Sylvain, 2009/03/06 20:50:46]

did we understand why it's creating a window instead of a tab? My testing were
not really useful. I'd like to understand the problem.

And if you feel like it, the test just above (SecondLaunch) had the same problem
IIRC, so you might want to do the samething there and reenable it. (That might
need refactoring a little bit your code though). If you don't want it's ok too.

But I would still like to understand the problem..

Other than that the code LGTM.

thanks

Nicolas

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