Panels refactor: Support browserless panels on Linux.

chrome/browser/ui/panels/panel_resize_browsertest.cc

Index: chrome/browser/ui/panels/panel_resize_browsertest.cc
diff --git a/chrome/browser/ui/panels/panel_resize_browsertest.cc b/chrome/browser/ui/panels/panel_resize_browsertest.cc
index 41c026ef6ea5c8a77a0e201041ac6bb4909cc378..7ca7ea32e84400e7c204cffb11f95d7de4b32f9b 100644
--- a/chrome/browser/ui/panels/panel_resize_browsertest.cc
+++ b/chrome/browser/ui/panels/panel_resize_browsertest.cc
@@ -8,9 +8,6 @@
 #include "chrome/browser/ui/panels/panel_manager.h"
 #include "chrome/browser/ui/panels/panel_resize_controller.h"
 
-// Refactor has only been done for Win and Mac panels so far.
-#if defined(OS_WIN) || defined(OS_MACOSX)
-
 class PanelResizeBrowserTest : public BasePanelBrowserTest {
  public:
   PanelResizeBrowserTest() : BasePanelBrowserTest() {
@@ -413,5 +410,3 @@ IN_PROC_BROWSER_TEST_F(PanelResizeBrowserTest, ResizeDetachedPanelToTop) {
 
   panel_manager->CloseAll();
 }
-
-#endif // OS_WIN || OS_MACOSX