https://bugs.webkit.org/show_bug.cgi?id=120006

Patch by Arpita Bahuguna <a.bah@samsung.com> on 2013-08-23
Reviewed by Ryosuke Niwa.

Source/WebCore: 

deleteSelectionCommand does not handle the case when a <br> element is
inlined after some non-textual content (input controls, image etc.).

When doing a back-delete at the start of a line following such a <br>
the two contiguous lines should merge and the <br> should get deleted.
Currently, even though the <br> is deleted, another placeholder <br>
is incorrectly inserted at the same point, thus effectively there is no
change.

We are incorrectly computing the inline <br> to be at the start of an
empty line even though the line is not empty.

Test: editing/deleting/delete-inline-br.html

* editing/DeleteSelectionCommand.cpp:
(WebCore::DeleteSelectionCommand::handleSpecialCaseBRDelete):
Adding a check to verify that the inline <br> is not on an empty line
if the end node is not a <br> element itself and it's previous sibling
is the start <br> element.

Basically we check whether there is another node (end node) following
the <br>, that the node is not a <br> itself, and that the end node's
previous node is the start <br>.

LayoutTests: 

* editing/deleting/delete-inline-br-expected.txt: Added.
* editing/deleting/delete-inline-br.html: Added.
Added a testcase that verifies that the caret is placed at the correct
position after performing a back-delete operation.

* editing/deleting/delete-before-block-image-2-expected.txt:
* platform/mac/editing/deleting/delete-br-004-expected.txt:
* platform/mac/editing/deleting/delete-br-005-expected.txt:
* platform/mac/editing/deleting/delete-br-006-expected.txt:
* platform/qt/editing/deleting/delete-br-004-expected.txt:
* platform/qt/editing/deleting/delete-br-005-expected.txt:
* platform/qt/editing/deleting/delete-br-006-expected.txt:
Rebaselining existing tests. No visual change in behavior for these tests.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@154479 268f45cc-cd09-0410-ab3c-d52691b4dbfc