Use the correct bounding rect in SVGInlineTextBox::nodeAtPoint

When writing-mode was unprefixed, SVGInlineTextBoxes started getting the
same treatment as their base-class, and hence we need to be careful when
we consider sizes for the inline boxes.
Use logicalWidth() and logicalHeight() instead of size().

BUG=587455

Review-Url: https://codereview.chromium.org/2124793002
Cr-Commit-Position: refs/heads/master@{#403913}
2 files changed