perfetto-ui: Stop frontend DOSing controller
perfetto-ui: Stop frontend DOSing controller

The front end sends a request for more data once as soon as it runs out
and then every 50ms thereafter. With many tracks requesting data at the
same time this can easily DOS the controller. As a temporary hack bump
the 50ms figure for summary tracks to 250ms. The real fix to batch
requests for more data and (ideally) have them driven by the controller.

Bug: 123616604
Change-Id: I0c9399527a70b84be74539812064b7a4a9c9ef31

google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto