Fix the Mac GN build.

This was broken in r287385 when the non_aura_sources was removed from chrome_browser_ui.

R=jamesr@chromium.org
TBR=jamesr

Review URL: https://codereview.chromium.org/468663002

Cr-Commit-Position: refs/heads/master@{#289314}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@289314 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/ui/BUILD.gn

@@ -242,9 +242,6 @@ static_library("ui") {
       sources += rebase_path(gypi_values.chrome_browser_ui_aura_non_chromeos,
                              ".", "//chrome")
     }
-  } else {  # Non-Aura.
-    sources += rebase_path(gypi_values.chrome_browser_ui_non_aura_sources,
-                           ".", "//chrome")
   }
   if (ui_compositor_image_transport) {
     deps += [ "//ui/gl" ]