Added pretty printers for some Ink Drop enums.

ui/views/animation/ink_drop_animation_ended_reason.h

Index: ui/views/animation/ink_drop_animation_ended_reason.h
diff --git a/ui/views/animation/ink_drop_animation_ended_reason.h b/ui/views/animation/ink_drop_animation_ended_reason.h
index fc2f359cef21bbb313c8dd5e8f41d517763e98c6..c61f37f314ee95f2c28ee3f2939546ec951f69ee 100644
--- a/ui/views/animation/ink_drop_animation_ended_reason.h
+++ b/ui/views/animation/ink_drop_animation_ended_reason.h
@@ -5,8 +5,11 @@
 #ifndef UI_VIEWS_ANIMATION_INK_DROP_ANIMATION_ENDED_REASON_H_
 #define UI_VIEWS_ANIMATION_INK_DROP_ANIMATION_ENDED_REASON_H_
 
+#include <iosfwd>
 #include <string>
 
+#include "ui/views/views_export.h"
+
 namespace views {
 
 // Enumeration of the different reasons why an ink drop animation has finished.
@@ -18,7 +21,12 @@ enum class InkDropAnimationEndedReason {
 };
 
 // Returns a human readable string for |reason|.  Useful for logging.
-std::string ToString(InkDropAnimationEndedReason reason);
+VIEWS_EXPORT std::string ToString(const InkDropAnimationEndedReason& reason);

[sky, 2016/05/04 23:43:42]

Generally we don't pass primitives by ref. For example, when was the last time
you saw a function take a const int&?

[bruthig, 2016/05/04 23:51:48]

Done.

+
+// 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(const InkDropAnimationEndedReason& reason, ::std::ostream* os);

[sky, 2016/05/04 23:43:42]

and here

[bruthig, 2016/05/04 23:51:48]

Done.

 
 }  // namespace views