Blink does not respect input.selectionStart and input.selectionEnd for some cases

LayoutTests/fast/forms/validationMessage-expected.txt

Index: LayoutTests/fast/forms/validationMessage-expected.txt
diff --git a/LayoutTests/fast/forms/validationMessage-expected.txt b/LayoutTests/fast/forms/validationMessage-expected.txt
index c073e6f1f841d6ad61496b4c884aef78f6fe9a95..a61436f279695af0a78696b09ff4602e8297d70e 100644
--- a/LayoutTests/fast/forms/validationMessage-expected.txt
+++ b/LayoutTests/fast/forms/validationMessage-expected.txt
@@ -28,7 +28,7 @@ input stepMismatch: Please enter a valid value. The two nearest valid values are
 input stepMismatch: Please enter a valid value. The two nearest valid values are 0.1 and 0.2.
 input stepMismatch: Please enter a valid value. The nearest valid value is 10.
 tooLong:
-input tooLong: Please shorten this text to 3 characters or less (you are currently using 5 characters).
+input tooLong: 

[tkent, 2014/06/01 23:40:55]

This looks wrong.

[harpreet.sk, 2014/07/02 10:13:05]

It is not wrong because for the given case caret was at the start of text when
delete command is called so nothing got deleted. So variable
m_lastChangeWasUserEdit remains false as no event occur. Now when the api 
HTMLInputElement::tooLong is called in this api they mention in a comment that 
 
  "return false for the default value or a value set by a script even if
   it is longer than maxLength."


bool HTMLInputElement::tooLong(const String& value, NeedsToCheckDirtyFlag check)
const
{
    // We use isTextType() instead of supportsMaxLength() because of the
    // 'virtual' overhead.
    if (!isTextType())
        return false;
    int max = maxLength();
    if (max < 0)
        return false;
    if (check == CheckDirtyFlag) {
        // Return false for the default value or a value set by a script even if
        // it is longer than maxLength.
        if (!hasDirtyValue() || !lastChangeWasUserEdit())
            return false;
    }
    return value.length() > static_cast<unsigned>(max);
}


That is the reason that the validation message is empty for this case. 
 

 input tooLong: Please shorten this text to 2 characters or less (you are currently using 3 characters).
 input tooLong: Please shorten this text to ٢ characters or less (you are currently using ٣ characters).
 textarea tooLong: Please shorten this text to 3 characters or less (you are currently using 5 characters).