Improve HTMLProgressElement exception messages.

This is the third file I've edited that threw exceptions on Infinity
or NaN. I've extracted those messages out into an ExceptionMessages
helper, and adjusted the existing tests accordingly (there was a typo
in VTTRegion's message that this CL fixes)

BUG=270033

Review URL: https://codereview.chromium.org/83363002

git-svn-id: svn://svn.chromium.org/blink/trunk@162542 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Get rid of ScopedStyleResolver::matchAuthorRules.

Inline it into StyleResolver::matchAuthorRules. This makes the StyleResolver
code easier to follow and makes it more clear that it's correct to pass
ignoreCascadeScope as the cascadeScope since there's inly one
ScopedStyleResolver.

Also rework some of StyleResolver::matchAuthorRules to reduce code duplication.

Review URL: https://codereview.chromium.org/79123003

git-svn-id: svn://svn.chromium.org/blink/trunk@162543 bbb929c8-8fbe-4397-9dbb-9b2b20218538
WebPasswordFormData: only ask for the 'id' attribute if there is one

Adding a hasID() guard to a idForStyleResolution() call.
This caused a crash before.

Tests for the crash are in https://codereview.chromium.org/82703003.

BUG=322242,282487

Review URL: https://codereview.chromium.org/83323002

git-svn-id: svn://svn.chromium.org/blink/trunk@162544 bbb929c8-8fbe-4397-9dbb-9b2b20218538