Add deprecation warning banner to App Launcher on Mac.

ui/app_list/test/run_all_unittests.cc

Index: ui/app_list/test/run_all_unittests.cc
diff --git a/ui/app_list/test/run_all_unittests.cc b/ui/app_list/test/run_all_unittests.cc
index eb2bf1f1c3eb5b9bc6f4ce1cf714a57eaaadcbc4..7b27bb9c877901c48d4f2776a2dc953520de13bf 100644
--- a/ui/app_list/test/run_all_unittests.cc
+++ b/ui/app_list/test/run_all_unittests.cc
@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "base/bind.h"
+#include "base/command_line.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/path_service.h"
@@ -24,12 +25,19 @@
 
 namespace {
 
+// Use the pattern established in content_switches.h, but don't add a content
+// dependency -- app list shouldn't have one.
+const char kTestType[] = "test-type";
+
 class AppListTestSuite : public base::TestSuite {
  public:
   AppListTestSuite(int argc, char** argv) : base::TestSuite(argc, argv) {}
 
  protected:
   void Initialize() override {
+    base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
+    command_line->AppendSwitchASCII(kTestType, "applist");
+
 #if defined(OS_MACOSX)
     mock_cr_app::RegisterMockCrApp();
 #endif