Links in platform apps should open in the system default browser.

chrome/browser/extensions/platform_app_browsertest_util.cc

Index: chrome/browser/extensions/platform_app_browsertest_util.cc
diff --git a/chrome/browser/extensions/platform_app_browsertest_util.cc b/chrome/browser/extensions/platform_app_browsertest_util.cc
index a722eb590f43465756c4dcc0d13fa7a596aad27a..2795469610a83fd9694b1618ccb95b8ad02a4001 100644
--- a/chrome/browser/extensions/platform_app_browsertest_util.cc
+++ b/chrome/browser/extensions/platform_app_browsertest_util.cc
@@ -10,6 +10,8 @@
 #include "chrome/browser/extensions/extension_function_test_utils.h"
 #include "chrome/browser/extensions/shell_window_registry.h"
 #include "chrome/browser/ui/browser.h"
+#include "chrome/browser/ui/browser_list.h"
+#include "chrome/browser/ui/browser_window.h"
 #include "chrome/browser/ui/extensions/application_launch.h"
 #include "chrome/browser/ui/extensions/shell_window.h"
 #include "chrome/common/chrome_switches.h"
@@ -22,11 +24,53 @@ namespace utils = extension_function_test_utils;
 
 namespace extensions {
 
+MockExternalUrlController::MockExternalUrlController() {
+}
+
+MockExternalUrlController::~MockExternalUrlController() {
+}
+
+content::WebContents* MockExternalUrlController::OpenURLFromTab(
+      content::WebContents* source,
+      const content::OpenURLParams& params) {
+  // Delete useless web content first to
+  // avoid a potential leak in a render process host.
+  delete source;
+
+  // Force to open in a new tab.
+  WindowOpenDisposition disposition = params.disposition;
+  content::OpenURLParams new_tab_params = params;
+  new_tab_params.disposition =
+      disposition == NEW_BACKGROUND_TAB ? disposition : NEW_FOREGROUND_TAB;
+  for (BrowserList::const_iterator i = BrowserList::begin();
+      i != BrowserList::end(); ++i) {
+    if ((*i)->is_type_tabbed()) {
+      Browser* browser = *i;
+      content::WebContents* new_tab = browser->OpenURL(new_tab_params);
+      browser->window()->Show();
+      return new_tab;
+    }
+  }
+  return NULL;
+}
+
+PlatformAppBrowserTest::PlatformAppBrowserTest() {
+}
+
+PlatformAppBrowserTest::~PlatformAppBrowserTest() {
+}
+
 void PlatformAppBrowserTest::SetUpCommandLine(CommandLine* command_line) {
   ExtensionBrowserTest::SetUpCommandLine(command_line);
   command_line->AppendSwitch(switches::kEnableExperimentalExtensionApis);
 }
 
+void PlatformAppBrowserTest::SetUpOnMainThread() {
+  mock_external_url_controller_.reset(new MockExternalUrlController());
+  ShellWindow::SetExternalUrlControllerForTesting(
+      mock_external_url_controller_.get());
+}
+
 const Extension* PlatformAppBrowserTest::LoadAndLaunchPlatformApp(
     const char* name) {
   content::WindowedNotificationObserver app_loaded_observer(