ALL-IN-ONE Introduce enum class TextAffinity

Source/core/editing/TextAffinity.h

Index: Source/core/editing/TextAffinity.h
diff --git a/Source/core/editing/TextAffinity.h b/Source/core/editing/TextAffinity.h
index efe33c72c62ad454b04cb9b40989f1e97d9dd4c6..05ba0adad3ffb5f78e69a2a866d253e4526ace69 100644
--- a/Source/core/editing/TextAffinity.h
+++ b/Source/core/editing/TextAffinity.h
@@ -36,22 +36,20 @@ namespace blink {
 // From NSTextView.h:
 // NSSelectionAffinityUpstream = 0
 // NSSelectionAffinityDownstream = 1
-// TODO(yosin) We should rename |UPSTREAM| and |DOWNSTREAM| to use
-// capitalized name.
-enum EAffinity { UPSTREAM = 0, DOWNSTREAM = 1 }; // NOLINT
+enum class TextAffinity { Upstream = 0, Downstream = 1 };
 
 } // namespace blink
 
 #ifdef __OBJC__
 
-inline NSSelectionAffinity kit(blink::EAffinity affinity)
+inline NSSelectionAffinity kit(blink::TextAffinity affinity)
 {
     return static_cast<NSSelectionAffinity>(affinity);
 }
 
-inline blink::EAffinity core(NSSelectionAffinity affinity)
+inline blink::TextAffinity core(NSSelectionAffinity affinity)
 {
-    return static_cast<blink::EAffinity>(affinity);
+    return static_cast<blink::TextAffinity>(affinity);
 }
 
 #endif