Avoid updating frame info while detached from activity
Avoid updating frame info while detached from activity

During the reparenting, the tab is detached from its
window android and for a while window_android stays as NULL.
During that time, we may still get frame updates. Avoid passing
these through if there is no window android

BUG=590697

Review URL: https://codereview.chromium.org/1746103002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#378289}

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