Move some methods from RawLayoutElementHelpers to LayoutElementHelpers.
This is part of a long-term plan to ensure layout never has access to
unwrapped pointers to DOM objects. The remaining methods on the
RawLayoutElementHelpers trait are harder to move, because of the lifetimes in
their signatures.
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Don't generate useless InheritTypes interfaces
Interfaces with no descendant need neither a Base trait nor upcast functions, and interfaces with no ancestors neither a Derived trait nor downcast functions.
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This is part of a long-term plan to ensure layout never has access to
unwrapped pointers to DOM objects. The remaining methods on the
RawLayoutElementHelpers trait are harder to move, because of the lifetimes in
their signatures.
HTMLTableSectionElement improvements
'thead' and 'tfoot' now create instances of HTMLTableSectionElement
HTMLTableSectionElement.rows has been implemented
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Interfaces with no descendant need neither a Base trait nor upcast functions,
and interfaces with no ancestors neither a Derived trait nor downcast functions.
Refactor FormControl trait
The trait is now implemented for HTMLFooElement instead of
&HTMLFooElement and does no longer require an impl body.
Suggested by @Manishearth
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Add form getters for additional elements; update test expectations
This adds form getters for fieldset, label, object, output, select and
textarea elements.
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Properly consider radio button groups
Radio button groups with missing or empty names are always the only element of their respective radio button group.
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webgl: Support texImage2D with a canvas as an argument
This involved some refactoring of the 2d context code, which lead to some more test passed there.
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This allows both boolean and string-type preferences. It
also implements a system where prefs that are read from a
configuration file can be reset back to their initial value,
which is useful in a number of cases e.g. when running tests
to ensure that each test starts with the same values for
the prefs.
