Added pretty printers for some Ink Drop enums.

ui/views/animation/ink_drop_state.h

 // Copyright 2015 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.
 
 #ifndef UI_VIEWS_ANIMATION_INK_DROP_STATE_H_
 #define UI_VIEWS_ANIMATION_INK_DROP_STATE_H_
 
+#include <iosfwd>
 #include <string>
 
 #include "ui/views/views_export.h"
 
 namespace views {
 
 // The different states that the ink drop animation can be animated to.
 enum class InkDropState {
   // The ink drop is not visible.
   HIDDEN,
@@ skipping 11 matching lines @@
   ALTERNATE_ACTION_TRIGGERED,
   // An active state for a view that is not currently being interacted with.
   // e.g. a pressed button that is showing a menu.
   ACTIVATED,
   // A previously active state has been toggled to inactive, e.g. a drop down
   // menu is closed.
   DEACTIVATED,
 };
 
 // Returns a human readable string for |state|.  Useful for logging.
-std::string ToString(InkDropState state);
+VIEWS_EXPORT std::string ToString(InkDropState state);
+
+// This is declared here for use in gtest-based unit tests but is defined in
+// the views_test_support target. Depend on that to use this in your unit test.
+// This should not be used in production code - call ToString() instead.
+void PrintTo(InkDropState ink_drop_state, ::std::ostream* os);
 
 }  // namespace views
 
 #endif  // UI_VIEWS_ANIMATION_INK_DROP_STATE_H_