* NewSpace::UpdateInlineAllocationInfo and PagedSpace::ComputeLimit were
closely related methods. Refactor these into a shared method in the
super class.
* refactor UpdateInlineAllocationInfo into SpaceWithLinearArea
* refactor StartNextInlineAllocationStep
* refactor PauseAllocationObservers

Bug: 
Change-Id: I898906d6228ff48e427367ef74e6dc77fb7a1837
Reviewed-on: https://chromium-review.googlesource.com/825591
Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50247}