Makes MaterialDesignController initialization explicit

ui/aura/test/aura_test_base.cc

Index: ui/aura/test/aura_test_base.cc
diff --git a/ui/aura/test/aura_test_base.cc b/ui/aura/test/aura_test_base.cc
index 7cbe9ac9870c8e82c5e370c29537d05dc3e6ce3c..0201d67175c55758db28ce76c43d0c98b5a40c72 100644
--- a/ui/aura/test/aura_test_base.cc
+++ b/ui/aura/test/aura_test_base.cc
@@ -9,6 +9,8 @@
 #include "ui/aura/test/test_window_delegate.h"
 #include "ui/aura/window.h"
 #include "ui/base/ime/input_method_initializer.h"
+#include "ui/base/material_design/material_design_controller.h"
+#include "ui/base/test/material_design_controller_test_api.h"
 #include "ui/compositor/test/context_factories_for_test.h"
 #include "ui/events/event_dispatcher.h"
 #include "ui/events/event_processor.h"
@@ -32,6 +34,10 @@ AuraTestBase::~AuraTestBase() {
 void AuraTestBase::SetUp() {
   setup_called_ = true;
   testing::Test::SetUp();
+  // ContentTestSuiteBase might have already initialized
+  // MaterialDesignController in unit_tests suite.
+  ui::test::MaterialDesignControllerTestAPI::UninitializeMode();
+  ui::MaterialDesignController::Initialize();
   ui::InitializeInputMethodForTesting();
   ui::GestureConfiguration* gesture_config =
       ui::GestureConfiguration::GetInstance();