Continue links

This isn't as simple as just dropping applyToAppendedContent = false
on LinkAnnotation, because browsers differ in their continuation
behavior. Firefox continues links, but Chrome doesn't.

To work around this, add a property indicating that the annotation
needs its continuation behavior to be forced.

Rename areAnnotationsCorrect() to needsPawn() accordingly.

Bug: 49931
Change-Id: Id6424af89c92bba2be87736e8a937e0f2067c007