IDL compiler: [LegacyImplementedInBaseClass]

For generated bindings, we already partly handle [LegacyImplementedInBaseClass]
in dependency resolution, but there's one twist: there's no separate
header for these.

This adds a test to compute_dependencies.py to omit this header.

BTW, new test file numbered as *3* b/c I'm doing [ImplementedAs]
in a separate CL, and that's more basic, but a little subtle,
so will post it next.

BUG=239771
R=haraken

Review URL: https://codereview.chromium.org/131193012

git-svn-id: svn://svn.chromium.org/blink/trunk@165425 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Make document.elementFromPoint() to work with OPTION elements

Since r159012, which makes document.caretRangeFromPoint() to work with :first-letter style by getting text offsets, document.elementFromPoint() uses RenderObject from HitTestResult rather than HitTestResult.innerNode(). This works fine for all cases except for node which doesn't have RenderObject, e.g. OPTION element.

This patch restores behavior before r159012 for document.elementFromPoint().
Note: :first-letter style doesn't affect result of document.elementFromPoint(), because it doesn't use text offsets.

BUG=335010
TEST=LayoutTests/fast/dom/Document/document-elementFromPoint-on-option-element.html

Review URL: https://codereview.chromium.org/137313007

git-svn-id: svn://svn.chromium.org/blink/trunk@165426 bbb929c8-8fbe-4397-9dbb-9b2b20218538