HTMLTextAreaElement.setSelectionRange should not change focus.

Source/core/html/HTMLTextFormControlElement.h

Index: Source/core/html/HTMLTextFormControlElement.h
diff --git a/Source/core/html/HTMLTextFormControlElement.h b/Source/core/html/HTMLTextFormControlElement.h
index 6a36f2b5fbe8af6e6d6ff4d97051e3467f2c583a..e27eabcf5a3ad2b1c1a7b4c4d34982ab353d83d2 100644
--- a/Source/core/html/HTMLTextFormControlElement.h
+++ b/Source/core/html/HTMLTextFormControlElement.h
@@ -42,6 +42,11 @@ class HTMLTextFormControlElement : public HTMLFormControlElementWithState {
 public:
     // Common flag for HTMLInputElement::tooLong() and HTMLTextAreaElement::tooLong().
     enum NeedsToCheckDirtyFlag {CheckDirtyFlag, IgnoreDirtyFlag};
+    // Option of setSelectionRange.
+    enum SelectionOption {
+        ChangeSelection,
+        NotChangeSelection
+    };
 
     virtual ~HTMLTextFormControlElement();
 
@@ -69,7 +74,7 @@ public:
     virtual void setRangeText(const String& replacement, ExceptionState&);
     virtual void setRangeText(const String& replacement, unsigned start, unsigned end, const String& selectionMode, ExceptionState&);
     void setSelectionRange(int start, int end, const String& direction);
-    void setSelectionRange(int start, int end, TextFieldSelectionDirection = SelectionHasNoDirection);
+    void setSelectionRange(int start, int end, TextFieldSelectionDirection = SelectionHasNoDirection, SelectionOption = ChangeSelection);
     PassRefPtrWillBeRawPtr<Range> selection() const;
 
     virtual void dispatchFormControlChangeEvent() OVERRIDE FINAL;