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

LayoutTests/fast/forms/validationMessage-expected.txt

 Test for validationMessage DOM property.
 
 On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
 
 
 input patternMismatch: Please match the requested format.
 input valueMissing: Please fill out this field.
 textarea valueMissing: Please fill out this field.
 select valueMissing: Please select an item in the list.
 input typeMismatch for incorrectValue: Please include an '@' in the email address. 'incorrectValue' is missing an '@'.
@@ skipping 10 matching lines @@
 input typeMismatch for foo@example.com,: Please enter a non-empty email address.
 input typeMismatch for foo@example.com,bar@..example.com: '.' is used at a wrong position in '..example.com'.
 input badInput: Please enter a number.
 badInput and valueMissing:
 PASS numberInput.validationMessage is nonRequiredBadInputMessage
 stepMismatch:
 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 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).
 PASS but.validationMessage is ''
 PASS anoninput.validationMessage is ''
 PASS happyFieldset.validationMessage is ''
 PASS happySelect.validationMessage is ''
 PASS happyOutput.validationMessage is ''
 PASS happyObject.validationMessage is ''
 PASS happyKeygen.validationMessage is ''
 PASS successfullyParsed is true
 
 TEST COMPLETE