Re-enable tabs_interactive_uitest for linux_aura

chrome/test/base/interactive_test_utils.cc

Index: chrome/test/base/interactive_test_utils.cc
diff --git a/chrome/test/base/interactive_test_utils.cc b/chrome/test/base/interactive_test_utils.cc
index e6681fbc986f4a061530b043a1d33ae2b5586372..bc410361433099579f56841954f6f34059fe22c7 100644
--- a/chrome/test/base/interactive_test_utils.cc
+++ b/chrome/test/base/interactive_test_utils.cc
@@ -23,6 +23,15 @@ bool GetNativeWindow(const Browser* browser, gfx::NativeWindow* native_window) {
 
 }  // namespace
 
+bool ActivateBrowserWindow(Browser* browser) {
+  if (!BringBrowserWindowToFront(browser))
+    return false;
+
+  BrowserActivationWaiter waiter(browser);
+  waiter.WaitForActivation();
+  return true;
+}
+
 bool BringBrowserWindowToFront(const Browser* browser) {
   gfx::NativeWindow window = NULL;
   if (!GetNativeWindow(browser, &window))