Introduce enum class TextAffinity as replacement of enum EAffinity

Source/core/editing/commands/InsertParagraphSeparatorCommand.cpp

Index: Source/core/editing/commands/InsertParagraphSeparatorCommand.cpp
diff --git a/Source/core/editing/commands/InsertParagraphSeparatorCommand.cpp b/Source/core/editing/commands/InsertParagraphSeparatorCommand.cpp
index 4032caa787348beb8f575961b56112db753f929b..259290de4dbca0f1d09f0a9a86fb5f75ef2a93a2 100644
--- a/Source/core/editing/commands/InsertParagraphSeparatorCommand.cpp
+++ b/Source/core/editing/commands/InsertParagraphSeparatorCommand.cpp
@@ -156,7 +156,7 @@ void InsertParagraphSeparatorCommand::doApply()
 
     Position insertionPosition = endingSelection().start();
 
-    EAffinity affinity = endingSelection().affinity();
+    TextAffinity affinity = endingSelection().affinity();
 
     // Delete the current selection.
     if (endingSelection().isRange()) {
@@ -258,7 +258,7 @@ void InsertParagraphSeparatorCommand::doApply()
 
         appendBlockPlaceholder(parent);
 
-        setEndingSelection(VisibleSelection(firstPositionInNode(parent.get()), DOWNSTREAM, endingSelection().isDirectional()));
+        setEndingSelection(VisibleSelection(firstPositionInNode(parent.get()), TextAffinity::Downstream, endingSelection().isDirectional()));
         return;
     }
 
@@ -303,7 +303,7 @@ void InsertParagraphSeparatorCommand::doApply()
         appendBlockPlaceholder(cloneHierarchyUnderNewBlock(ancestors, blockToInsert));
 
         // In this case, we need to set the new ending selection.
-        setEndingSelection(VisibleSelection(insertionPosition, DOWNSTREAM, endingSelection().isDirectional()));
+        setEndingSelection(VisibleSelection(insertionPosition, TextAffinity::Downstream, endingSelection().isDirectional()));
         return;
     }
 
@@ -321,7 +321,7 @@ void InsertParagraphSeparatorCommand::doApply()
         // If the insertion point is a break element, there is nothing else
         // we need to do.
         if (visiblePos.deepEquivalent().anchorNode()->layoutObject()->isBR()) {
-            setEndingSelection(VisibleSelection(insertionPosition, DOWNSTREAM, endingSelection().isDirectional()));
+            setEndingSelection(VisibleSelection(insertionPosition, TextAffinity::Downstream, endingSelection().isDirectional()));
             return;
         }
     }
@@ -428,7 +428,7 @@ void InsertParagraphSeparatorCommand::doApply()
         }
     }
 
-    setEndingSelection(VisibleSelection(firstPositionInNode(blockToInsert.get()), DOWNSTREAM, endingSelection().isDirectional()));
+    setEndingSelection(VisibleSelection(firstPositionInNode(blockToInsert.get()), TextAffinity::Downstream, endingSelection().isDirectional()));
     applyStyleAfterInsertion(startBlock.get());
 }