Ozone Linux: Fix linker errors in interactive_ui_tests

chrome/browser/ui/views/tabs/tab_drag_controller_interactive_uitest.cc

 // Copyright (c) 2012 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 "chrome/browser/ui/views/tabs/tab_drag_controller_interactive_uitest.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 
@@ skipping 291 matching lines @@
 };
 
 // Factory for creating a TestDesktopBrowserFrameAura.
 class TestNativeBrowserFrameFactory : public NativeBrowserFrameFactory {
  public:
   TestNativeBrowserFrameFactory() {}
   ~TestNativeBrowserFrameFactory() override {}
 
   NativeBrowserFrame* Create(BrowserFrame* browser_frame,
                              BrowserView* browser_view) override {
+#if defined(USE_OZONE)

[sky, 2016/11/04 21:33:02]

Without TestDesktopBrowserFrameAura TabDragCaptureLostTest isn't useful. So, I
would rather see you DISABLE said test with a comment and a bug.

[Tom (Use chromium acct), 2016/11/04 21:54:21]

That would not fix the linker error.  The error is because there's no
DesktopBrowserFrameAura* on Linux Ozone builds atm.  Maybe I can stub one out as
an alternative?

[sky, 2016/11/04 23:15:39]

If that's the case, don't you need an ifdef around TestDesktopBrowserFrameAura?
I'm ok with that, just trying to understand.

[Tom (Use chromium acct), 2016/11/04 23:34:05]

Oops, I meant there's no CreateBrowserDesktopWindowTreeHost function, and maybe
I can stub out a BrowserDesktopWindowTreeHostOzone

The linker error I get is:
../../chrome/browser/ui/views/frame/desktop_browser_frame_aura.cc:54: error:
undefined reference to
'BrowserDesktopWindowTreeHost::CreateBrowserDesktopWindowTreeHost(views::internal::NativeWidgetDelegate*,
views::DesktopNativeWidgetAura*, BrowserView*, BrowserFrame*)'

TestDesktopBrowserFrameAura is a subclass of DesktopBrowserFrameAura, which has
DesktopBrowserFrameAura::InitNativeWidget which calls
CreateBrowserDesktopWindowTreeHost.

So even though we compile desktop_browser_frame_aura.cc, we never use it in the
ozone build, so by some crazy linker magic it all works ¯\_(ツ)_/¯

+    NOTIMPLEMENTED()
+        << "For Ozone builds, only --mash launch is supported for now.";
+    return nullptr;
+#else
     return new TestDesktopBrowserFrameAura(browser_frame, browser_view);
+#endif
   }
 
  private:
   DISALLOW_COPY_AND_ASSIGN(TestNativeBrowserFrameFactory);
 };
 
 class TabDragCaptureLostTest : public TabDragControllerTest {
  public:
   TabDragCaptureLostTest() {
     NativeBrowserFrameFactory::Set(new TestNativeBrowserFrameFactory);
@@ skipping 2176 matching lines @@
                         DetachToBrowserTabDragControllerTest,
                         ::testing::Values("mouse", "touch"));
 INSTANTIATE_TEST_CASE_P(TabDragging,
                         DetachToBrowserTabDragControllerTestTouch,
                         ::testing::Values("touch"));
 #else
 INSTANTIATE_TEST_CASE_P(TabDragging,
                         DetachToBrowserTabDragControllerTest,
                         ::testing::Values("mouse"));
 #endif