This CL depreciates the TransitionView Class of the
app model to handle map transition only within map
model. It isolates the Map Panel to comply web
component standards.

Bug: v8:10667, v8:10644

Change-Id: Idf8ca58744aacd0159ee4af6e71886374385377e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2300541
Commit-Queue: Zeynep Cankara <zcankara@google.com>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68902}