Stricter treatment of SVGSVGElement::m_useCurrentView

m_useCurrentView being true implies that m_viewSpec is non-null. Perhaps
defensively, most code that checks it is written in a way such that it
expects that m_viewSpec can be null if m_useCurrentView is true - which
is not the case, and adds unnecessary code.
Instead change the code to adhere to the rule above, and assert that in
the various places instead.
Also add some checks of the invariant in methods that set the flag and
m_viewSpec. Refactor SVGSVGElement::setupInitialView to avoid the need
to sprinkle invariant checks "all over" it.


Cr-Commit-Position: refs/heads/master@{#415346}
1 file changed