Added accessibility notification from Blink when spelling mistakes are detected.

Added accessibility notification from Blink when spelling mistakes are detected.

I still have to figure out how to test this properly and also ask for a review from Yosin@, but please have a first look to tell me if it's in the right direction.
BUG=640479
R=dmazzoni@chromium.org

[nektarios, 2016-08-25 01:52:22]

nektar@chromium.org changed reviewers:
+ dtseng@chromium.org

[nektarios, 2016-08-25 01:52:39]

Preliminary.

[dmazzoni, 2016-08-25 15:19:04]

https://codereview.chromium.org/2268183006/diff/1/third_party/WebKit/Source/c...
File third_party/WebKit/Source/core/editing/spellcheck/SpellCheckRequester.cpp
(right):

https://codereview.chromium.org/2268183006/diff/1/third_party/WebKit/Source/c...
third_party/WebKit/Source/core/editing/spellcheck/SpellCheckRequester.cpp:305:
axObjectCache->handleEditableTextContentChanged(m_processingRequest->rootEditableElement());
Please add a new AXObjectCache function specifically for this, like
handleTextMarkersChanged

In a contenteditable, what node are the text markers attached to? Are they
attached to the root editable element, or to a child like a static text element?

If it's a child, then we need to fire a notification on that child also.

[dmazzoni, 2016-08-25 15:20:37]

As for testing, could you use
LayoutTests/accessibility/contenteditable-notifications.html as a guide and
write something along those lines?